New Additions – July, 2024
New Discoveries of Early Fossil Mammals
Descriptions of new finds of spectacular early fossil mammals:
Repenomamus, the dinosuar eater and largest Mesozoic mammal
Hadrocodium, the smallest Mesozoic mammal
Eomaia, the earliest eutherian mammal
and others
Abiogenesis
Were Bacteria the First Forms of Life on Earth? : by Daniel Jeffares and Anthony Poole. Human cells can reveal evolutionary history because they:
Contain molecular fossils.
Exhibit mechanisms that were in development when life began.
Indicate that ancient organisms may be more complex than first thought.
Mitochondria Project : Database for mitochondria-related genes, proteins and diseases. The mitochondria that fuel cellular activities tote their own set of genes, betraying their origins as bacterial interlopers. Whether you're interested in humans, mice, or other model organisms, you can find sequence and function information for genes in the mitochondrial DNA and for related genes in the cell's nuclear DNA. The site also catalogs diseases triggered by mutations in these genes.
Anthropology
European Prehistoric Art : They're the original old masters: early European artists who began adorning caves, stones, cliff faces, and other surfaces more than 30,000 years ago. This site documents the diversity of art from the Stone Age through the Iron Age.
MIT CourseWare in Cultural Anthropology : Magic, Witchcraft, and the Spirit World, and Anthropology of the Middle East.
Biochemistry
[ No additions this period ]
Biology
Bacteria – Animal Symbiosis : Learn about four symbiotic relationship at this site. The bobtailed squid, bacterial denizens of the leech's gut and the bugs that feed aphids their essential amino acids are reviewed. Each account features a bibliography and links to labs studying the symbiosis.
MIT CourseWare in Biology : Introduction to Biology, Introduction to Experimental Biology, Genetics, Molecular Biology and Graduate Biochemistry
Developmental Physiology : Tackling questions such as the origin of the heartbeat and the effect of temperature on muscle growth, developmental physiology is where embryology meets molecular biology and biochemistry.
Neuroscience Resources : General links for neurobiology students.
Sizing Up the Brain : Mutations that produce small brains may reveal how human intelligence evolved.
AFC Signaling GatewayThis is a comprehensive and up-to-the-minute resource for anyone interested in cell signaling. It is a collaboration between academia and scientific publishing and is designed to facilitate navigation of the complex world of research into cellular signaling. Information and data presented here are freely available to all.
Motion Integration : (Requires QuickTime plug-in). To walk down a busy sidewalk without bumping into people, your visual system has to correctly chart a flurry of motion. This web tutorial uses a series of animations to illustrate the challenges that the visual system faces to interpret moving objects in a way that makes sense.
Skeletal Gene Database : From the shape of our cheekbones to the kinks in our toes, genes shape our skeletons. The Skeletal Gene Database at the National Institutes of Health holds information on some 200 genes involved in normal and abnormal bone and cartilage formation in mice and humans.
The Avian Leg : The bird's leg has the typical vertebrate pattern of femur, tibia, and fibula. No, bird's legs to not bend the wrong way. That's the ankle that looks like an elevated knee. Bone by bone, compare the avian and mammalian legs, starting from the hip joint and working downward. Check out Avian Skeletal Adaptations and these Fish-Bird-Cat-Dog Comparisons. Then you might Click on the Bird Skeleton. The study and reconstruction of the chicken skeleton is very interesting, inexpensive, and down right tasty. And this illustration shows that Even Dino Legs are Like Chickens' and Our's. Finally Avian Anatomy and Morphology will help you discover how many aspects of birds have evolved to better fit them for conditions of life and flight.
Dream Anatomy: A National Library of Medicine Exhibit : You won't see an image like this in Gray's Anatomy. But early anatomy texts often depicted smiling, cavorting bodies flaunting their dangling innards and exposed muscles, as in this 1681 sketch by artist John Browne. Although it seems macabre today, the cadaver at play convention was one step toward the modern scientific drawing. Featuring works from ancient Egypt to the present day, the exhibit highlights the trend toward greater realism and accuracy, led by scientists and artists such as the Italian anatomist Andreas Vesalius. His meticulous 1543 text is considered the first modern anatomy book. Although the physical exhibit ends next July, the Web version will continue to grow, says curator-historian Michael Sappol.
Jan Swammerdam : This 17th century Dutch microscopist, made major discoveries in medicine and anatomy. His greatest contribution to biology was his understanding of insect development and his demonstration that the same organism persists through its various stages.
Biology — Natural & Sexual Selection
Natural Selection : In modem evolutionary genetics, natural selection is defined as the differential reproduction of genotypes (individuals of some genotypes have more offspring than those of others). Natural selection would be occurring if, in a population of Jungle Fowl (the wild progenitors of chickens), single-comb genotypes were more reproductively successful than pea-comb genotypes.
Coevolution : Birds, of course, are presumed to be directly involved in many coevolutionary relationships with their competitors, predators, prey, and parasites. The relationship of seed-hoarding Clark's Nutcrackers and Pinyon Jays with Pinyon Pines is a relatively well-studied example; and the evolution of long bills and sickle-shaped bills in some Latin American Hummingbirds which match the long or sharply curved flowers from which they sip nectar (and which they pollinate) is another obvious case of coevolution.
Size and Sex in Raptors : In most birds, males are larger than females, but in some birds, such as many shorebirds and birds of prey, the reverse is true. No one is certain why there is this reversed sexual size dimorphism in raptors, but a number of interesting hypotheses have been advanced.
Sexual Selection : In one kind of sexual selection, members of one sex create a reproductive differential among themselves by competing for opportunities to mate. The winners out-reproduce the others, and natural selection occurs if the characteristics that determine winning are, at least in part, inherited. In the other kind of sexual selection, members of one sex create a reproductive differential in the other sex by preferring some individuals as mates. If the ones they prefer are genetically different from the ones they shun, then natural selection is occurring.
Biology — Eyes
Ask A Biologist – Seeing Color : When the light enters our eyes, special cells tell our brains about the light. These cells are called photoreceptors. Light is made of little bits called photons. When the sun shines, trillions and trillions of these little bits of light fall on the earth. The photons bounce off of almost everything and some of them enter our eyes. Those bits that enter our eyes allow us to see.
Third Eye Works Before Real Eyes Form : Tadpoles – like other amphibians and reptiles – have a "pineal eye" in the top of their heads, capable of detecting changes in light but not of forming images.
Blind Mice See : Although unable to see, mice lacking rods and cones in their retinas can tell day from night. And their pupils still respond to bright light.
Carl Zimmer on Alpha-crystallins : Alpha-crystallins, which are found in all vertebrate eyes, are strikingly similar to the common molecules known as heat-shock proteins. Heat-shock proteins are crucial to every organism on earth; in our own bodies they are at work in almost every cell.
Evolution of Vision – From Dinosaurs to Mammals : Some millions of years ago the gene controlling the synthesis of long wavelength photopigment underwent certain mutations in some primates including our ancestors. A duplication of the original long wavelength gene resulted in 2 genes. They are now producing photo-pigment molecules with slightly different amino acid sequence and thus spectral maxima for red and green. This lead to a trichromatic state and extended the ability of these primates for distinguishing hues towards longer (yellow – red) wavelengths.
Evolution of Activity Patterns and Chromatic Vision in Primates : Morphometrics, Genetics and Cladistics. .pdf file This is a thorough scientific analysis of the relationship of vision in primates, including cladistic trees based on those relationships.
Webvision Home Page : The organization of the vertebrate retina. A thorough look at the biology of the human eye.
Triassic Reptile Saw Red : Scientists have resurrected a 240-million-year-old eye protein that sees dim light.
Biology — Teaching Evolution
Lesson Plan: Fossils and Dinosaurs : Although this lesson is designed for grades 3-5, it can easily be modified to include grades 6-8. Students examine what can be learned from fossils and how fossils are formed.
Lesson Plans: Evolution/Fossils/Rocks : Choose from several lessons that help students investigate fossils and evolution.
Critical Thinking : This is a collection of links to sites that promote and teach reasoning and that uncover sloppy and dubious arguments. There are texts and tutorials on critical thinking to catalogs of logical fallacies and exposés of quackery, as well as selections from English scientific philosopher Francis Bacon and late evolutionist Stephen Jay Gould.
MIT CourseWare : Bucking the trend in for-profit distance education, MIT decided that it would share nearly all of its course materials on a free website. This is the first installment of resources for the project covering more than 30 undergraduate and graduate classes in 17 departments.
Educational Biology Site : Here, biology comes alive through photography. Geared toward teaching middle and high schoolers, it consists of a series of photo galleries. Students learn as they marvel at the images, and factoids roll out from under each photo as the cursor moves. Each gallery is supplemented with interactive essays that explain how each animal adapts to its environment.
Ask A Biologist : This is an educational resource for students K-12 and their teachers. Under Experiments and Stuff you will find Backyard Experiments, Guessing Games, Puzzles, Quizzes and Young Scientists Coloring Pages. Submit questions and get feedback.
Learn Evolution in Geography Class : Many aspects of evolution are related to geography. This introductory course is easy to understand. Find out why the term, missing links, is so misleading now.
Teaching Evolution in the United States : A state-by-state evaluation of the treatment of evolution in science standards. Tables show areas in which various state standards are lacking – and allow comparison of a state's evolution grade with the evaluation of its overall science standards.
Eugenie Scott Live : Listen to a lecture about teaching evolution at the high school or college level.
Education Index Page : A very useful collection of thought-provoking essays for biology teachers.
Footsteps Through Time : This is an exhibit of the Museum of Man in Balboa Park in San Diego. It is sending kits to all public middle schools in the county to help teachers meet California science curriculum teaching standards. The materials were developed in conjunction with the museum's exhibit, documenting four million years of human evolution.
Biotechnology
Agricultural Biosafety : Now you can keep abreast of which transgenic crops – from rice and corn to papaya and tobacco – have received approval for human or animal consumption or for release in more than two dozen countries worldwide. Agbios, an independent company in Canada, provides information to regulators, policymakers, and academics, maintains a crop database that allows the user to search by criteria such as species, traits (for example, male sterility or delayed ripening), and regulatory status. The site also includes risk-assessment training modules, based on a real-world case of insecticide-producing maize, to help readers understand the product-approval process. There's also a bibliographic database with more than 1400 papers about biosafety and genetically modified organisms.
Books
Review by Douglas Futuyma : Toward a New Philosophy of Biology
At the Water's Edge: Fish with fingers, whales with legs, and how life came ashore but then went back to sea. In this book science journalist Carl Zimmer brings his reportorial skills and impressive literary talents to bear upon one of evolution's most important questions. He presents an exquisite, up to date, narrative on the evolution of tetrapods, emerging from the water as amphibians, continuing to evolve into reptiles, birds and mammals, and then returning to the sea as mammalian cetaceans. Included in the story are fossil discoveries of the last 25 years – the finding of whales that walked on land and their gradual change to creatures of the deep sea, and the closing of the infamous time of absence known as Romer's Gap. This is a stunning narrative.
Botany
USA Threatened & Endangered Plants : Recently revamped with state listings as well as federal ones, the database serves up a profile for each plant that includes habitat, range, and taxonomy as well as links to more info. The listing is a branch of the USDA's sprawling PLANTS website.
Cell Biology
Atlas of Histology : These two Web sites are brimming with photos of cell types and organ systems. With more than 3000 slides, users can zoom in on finer and finer images to see the details of structures. The Virtual Slidebox offers similar images that can be magnified up to 40 times.
Chemistry
Chemistry Applets : These six Java applets are like a virtual chemistry set, letting undergrads absorb principles by messing around. The simulations explore subjects such as the second law of thermodynamics, the reversibility of reactions, and statistical mechanics.
MIT CourseWare in Chemistry : Physical Chemistry: Quantum Mechanics (see also Biology).
Creationism and Intelligent Design
Ken Miller - Paley in a Test Tube : Listen to a wide-ranging lecture on evolution and refutation of Behe's Darwin's Black Box. Also hear Miller discuss Darwin, God, and the Human Genome.
Science and Faith: a Panel Discussion : For many people of various faiths, support for the scientific theory of evolution has not supplanted their religious belief. And throughout the modern Judeo-Christian tradition, leaders have asserted that evolutionary science offers a valid perspective on the natural world. They say that evolution is consistent with religious doctrine and complements, rather than conflicts with, religion.
Intelligent Design? : A special report reprinted from Natural History magazine. Three proponents of Intelligent Design (ID) present their views of design in the natural world. Each view is immediately followed by a response from a proponent of evolution (EVO). The report, printed in its entirety, opens with an introduction by Natural History magazine and concludes with an overview of the ID movement. The authors who contributed to this Natural History report are:
Richard Milner and Vittorio Maestro, ed. (introduction)
Michael J. Behe, (ID) and Kenneth R. Miller, (EVO)
William A. Dembski, (ID) and Robert T. Pennock, (EVO)
Jonathan Wells, (ID) and Eugenie C. Scott, (EVO)
Barbara Forrest, (overview)
Separating Religious Fundamentalist Science from Science : by Tim M. Berra. Evolution is attacked by religious fundamentalists, a small minority, who:
Refute scientific evidence using Scripture as their sole argument.
Use political lobbying to force their beliefs on the general public.
Promote confusion and science illiteracy to mask their intentions.
Black Sea Flood? : Why the Black Sea is not the Site of Noah's Flood. Glenn Morton discusses the situation in 1998 and here updates his views to reflect more recently published research.
Current News & Science Journals
[ No additions this period ]
Darwiniana, Eugenics, Sociobiology
Map of the Voyage of the Beagle
Darwin Correspondence Project : A new undertaking begun in December 2024, it will gradually place all of the Darwin correspondence online in searchable databases. Currently, lists are available of the names of 2,000 persons with whom Darwin is known to have exchanged more than 20,000 cards and letters.
Michael Ruse on Darwinism : Listen to a lecture in which Ruse compares professional and popular Darwinism and aspects of social aspects of Darwinian evolution.
Dating
Consistent Radiometric Dates : by Joe Meert. If radiometric decay rates are not constant and rocks behave as open systems, it would be the exception, not the rule, for ages to agree with one another. Gives examples of radiometric dating of the same rocks (using different isotopic methods).
Accuracy of Fossils and Dating Methods : by Michael Benton. Fossil dating is accurate since the method follows strict scientific guidelines:
The age of rocks around a fossil can be considered.
Mathematical calculations are used.
The state of decay, carbon-14, and isotopes figure in calculations.
Tree of life relationships often help sort the dates.
Ecology
Biodiversity Hotspots : Evolution plays favorites. Only 25 small areas, known as biodiversity hotspots, boast nearly half of the world's plant species and more than one-third of its vertebrates. Visit the hotspots with this new online atlas.
Coral Bleaching Indices : This site uses satellite measurements of sea temperatures to help scientists pinpoint where corals are at risk. Monitoring 24 reefs in the Indian, Pacific, and Atlantic oceans, the site gives each reef a vulnerability score based on how long water temperature stays above the average maximum for the time of year. Links take you to global maps of bleaching hot spots and animations that chart their changing locations.
GreenHouse Gas Online : For teachers and students, there are backgrounders on topics such as the possible effects of global warming, sources of greenhouse gases, and carbon dioxide sinks such as plants and the ocean that store the molecule. The site also links to news stories on pollution and climate change, such as the recent discovery of a brown cloud of airborne gunk hovering over Asia.
Coral Reef Information System : Coral reefs are the rainforests of the ocean: diverse, showy, and abused. Reef experts and curious visitors will find a trove of data about these rich ecosystems and the threats they face. There's also a guide to nearly 3300 coral-inhabiting fishes from around the world. To get eye to eye with some reef inhabitants, plunge into the photo library of 800 images.
Coral Reef Glossary
Undersea Acoustic Monitoring Program : Plug in your desired latitude and longitude to receive hydrophone data from the East Pacific Rise, Mid-Atlantic Ridge, or North Pacific. Learn about undersea earthquakes and monitor marine mammals. See spectrograms of sounds produced by a blue whale compared to repeated noise from an air gun, fired in Nova Scotia but recorded more than 3500 kilometers away on the Mid-Atlantic Ridge. The site also includes a detailed underwater acoustics tutorial. A sister site offers a similar tutorial geared toward a more general audience. Sound in the Sea.
Passive-Microwave Earth Science : By detecting microwaves that radiate naturally from Earth and scatter in the atmosphere, satellites can build a picture of temperatures, rain and snow cover, and wind speed. Track the latest typhoon or hurricane churning across the Pacific or the Caribbean. Global maps of sea surface temperature, oceanic wind speed, and precipitation go back 5 years.
Ocean Biogeographic Information System : Data on marine species can be as widely scattered and hard to locate as giant squid. OBIS lets you trawl 12 marine databases for collection records. The project is part of the international Census of Marine Life, whose goal is to compile a complete catalog of marine species, their distribution, and their abundance.
The Sixth Extinction : by Niles Eldredge. Can we stop the devastation of our planet and save our own species? We are in a biodiversity crisis -- the fastest mass extinction in Earth's history, largely due to:
Human destruction of ecosystems.
Overexploitation of species and natural resources.
Human overpopulation.
The spread of agriculture.
Pollution.
The footnotes and links on this page make up a very nice, but sad, course about the biodiversity crising that is not just coming, but is here now.
Education
[ No additions this period ]
Essays
Gulick, Belt, Delboeuf, Catchpool : (four authors in 1800s may be of interest). [Read before the Linnean Society of London, November 21, 1872.]
Missouri Botanical Garden Photo Essays : Taxonomists still have plenty of work to do because millions of species remain undescribed. These essays supply background info on natural history, geology, the origins of various species, and the human impact on local biodiversity.
Ernst Mayr — Curriculum Vita : A list of awards, profressional positions, honorary doctorates and affiliations.
Richard Dawkins: The joy of living dangerously : Forget exams and league tables. Real education, exemplified by a maverick headmaster almost 100 years ago, is about the power of knowledge and the thrill of discovery.
Sciences Quotation File Part I: Evolution and Creationism : Many quotations from the writings of Steve Gould, with a nice collection from others such as Niles Eldredge and Isaac Asimov.
Nobel Centennial Symposia : Features video of all 21 speakers at the centennial symposium on how genomics is revolutionizing fields from developmental biology to medicine to evolution. The lectures provide scientists and students with a glimpse at the future.
Where'd You Get Those Peepers : by Richard Dawkins. There has been enough time for eyes to evolve from scratch 1,500 times within any one lineage. Time, far from stretching credulity with its vastness, turns out to be too short for geologists to measure! It is a geological blink.
Mill Hill Essays 2024 : Annual volumes since 1995 each contain a handful of essays explaining much of modern scientific discovery. This is a nice education stop when you have the time to browse and contemplate.
Eugenics
[ No additions this period ]
Evolution
Evolution Evolving : John Cairns' postulated that bacterial cells, in effect, mysteriously know in advance which mutations are likely to benefit them. Then, when investigators stress the cells by starving them, the bacteria tip fate's scales so that rare beneficial mutations happen more often than chance would allow.
Unpredictable Evolution in a 30-Year Study of Darwin's Finches : Grant, P. R., Grant, B. R., Science 296 (5568):707-711 (2002). Evolution can be predicted in the short term from a knowledge of selection and inheritance. However, in the long term evolution is unpredictable because environments, which determine the directions and magnitudes of selection coefficients, fluctuate unpredictably. Read online by subscription or see at your local library.
Catalyst Science Story Archive : Transcripts and images from each story on Catalyst will be available after the program goes to air each Thursday. There is a wide variety of subject matter covered by the series. You might want to browse for something of interest.
Principles of Evolution and Systematics : This is a good outline course in evolution, with many photos and graphics accompanied by limited text.
Evolution of Sexual Reproduction : Sexual reproduction is favored by many organisms. New combinations of genes can be assembled on the same chromosomes through recombination. Independent assortment during meiosis, which changes combinations of chromosomes, generates endless genetic diversity.
International Journal of Organic Evolution : The journal Evolution is available free, online. All articles are available back through the year 2024.
Retroviruses Demonstrate Human Evolution : Phylogenies of ancient endogenous retrovirus sequences shows how an ERV locus shared by two or more species is descended from a single integration event, proving that the species share a common ancestor into whose germ line the original integration took place.
Tool Use in New Caledonian Crows : In the wild, the crows make a wide variety of tools from a number of different materials, and they will also readily do so in captivity, even with unfamiliar materials.
Genetics
Mendelian Inheritance in Animals : Dogs and cats can have the blood-clotting disease hemophilia. Camels sometimes fall victim to cardiomyopathy, a potentially lethal enlargement of the heart muscle, and koalas are susceptible to diabetes. Searchable by disease and by species, the bibliography includes publications on 100+ mammals, birds, reptiles, fishes, and other beasts.
Tracing Ancestors at Oxford : Almost everyone in Europe, or whose maternal roots are in Europe, is descended from one of only seven women. If your roots are in Europe, you will discover which of these women is your ancestor and find out about her World. In other parts of the World, twenty nine equivalent clans have been identified so far. If your maternal roots lie outside Europe, you can find which one of these you belong to and how you are connected to all the other clans. Two other companies offering different genetic services are DNAPrint genomics and Family Tree DNA.
Ape Genome Sequencing : An interesting website with a great deal of genetic data comparing different primates, including humans. For each genetic comparison evolutionary trees are created. Select the genes you wish to compare and see the results.
Species: Comparing Their Genomes : Mapping the genome of different species reveals that:
All living things share parallel genes.
The genome of other species can be used for human disease research.
Many diseases are caused by defective genes or proteins.
So far, the mouse offers the best insight into human disease.
Beautiful Buttocks : Solid Gold is the first known sheep to have the callipyge condition – Greek for beautiful buttocks – and his descendants are shedding light on genomic imprinting, the difference in expression of a gene depending on which parent transmits it.
Bioinformatics Applications and Tools : See PipMaker and MultiPipMaker which are used to compute alignments of similar regions in two DNA sequences. This page illustrates the utility of PipMaker with several examples, most of which compare a region of the human genome with the homologous region from the mouse. See these PipMaker Examples
Hox Proteins Have Evolved : Adult insects have six legs. No more, no less. But the class Insecta is descended from multilimb ancestors, and most other living arthropods, including Insecta's closest living relative, the Crustacea, usually have at least five pairs of legs or leg-like appendages. How insects lost their limbs has interested those in the burgeoning field of evo-devo, the study of developmental evolution. This news story is based largely on 3 items that appeared in the Feb. 21 issue of Nature. The first is a News and Views article by
M. Levine, How Insects Lose Their Limbs, on pp. 848-9. This is followed by two research papers on pp. 910-917. R. Galant and S.B. Carroll write on the Evolution of a Transcriptional Repression Domain in an Insect Hox Protein, while M. Ronshaugen et al. report on Hox Protein Mutation and Macroevolution of the Insect Body Plan. Nature is available by online sunscription or at academic libraries in the USA and many local libraries in the UK.
Gene Expression in Drosophila Embryogenesis : Like musicians, the genes that mold a growing fly need to have exquisite timing. Starting or stopping at the wrong point can lead to discordant results. The site has digital images for activity patterns of 1354 of the fly's 13,600 genes. Each report shows where the gene is turned on during different stages of development and also presents DNA microarray expression profiles.
Hierarchical Classification of Proteins : For more than 100,000 proteins, a data card lists each molecule's amino acid sequence, identifies functional regions, and charts the taxonomy of the organism it comes from. Compare each protein to other members of its immediate family or contrast different groups, which might help deduce the function of molecules or tease out evolutionary trends.
Geology and Earth Sciences
Descent to the Mid-Atlantic Ridge : This is the story of a research cruise out of the Woods Hole Marine Laboratory. Reporting from the middle of the Atlantic Ocean, an international team of scientists spent almost four weeks exploring an unusual mountain called the Atlantis Massif, part of the extensive Mid-Atlantic Ridge which, at a length of nearly 10,000 km., is one of the earth's largest undersea mountain ranges . In an area at 30 degrees north on the ridge the research team uses several high-tech tools to study the smooth and corrugated top of the mountain as well as its steep slopes where landslides and faults expose rocks that are usually hidden deep beneath the seafloor. They investigated the processes that might have brought these deep rocks to the surface in the form of an unusually large and elevated undersea mountain. The research submersible Alvin was used on this expedition.
Dating Exhibit : Relative and Absolute dating methods.
Geochemistry of Oceans Rocks : Bore into this geological chemistry database for nearly 100,000 igneous rock samples collected from the ocean floor and from islands around the globe. The site provides concentrations of common and trace elements and of radioactive isotopes, and you can customize your search by element, location, and type of formation.
Permafrost : A new map of permafrost indicates it underlies approximately 22.79 million square kilometers (about 23.9 percent of the exposed land surface) of the Northern Hemisphere. It occurs as far north 84°N in northernmost Greenland, and as far south as 26°N in the Himalayas.
Introduction to Physical Geography : 37 lectures take you from an introduction to the science of geography through geology and evolution to glaciation and much more.
Volcano Cams Around the World : Watch live eruptions at this site from the U.S. Geological Survey, which links to more than 40 Webcams that are trained on active volcanoes around the world.
National Earthquake Information Center : Few earthquakes pack the destructive power of the 1994 Northridge quake, which amputated this freeway overpass in Southern California. But smaller temblors rattle parts of the globe every day. Find out where the ground is rumbling with near-real-time reports from this site by the USGS.
Weather Photography : This online gallery showcases hundreds of photos, from a cloud menagerie to shots of the green flash, a rare burst of color on the setting sun caused by refraction. Captions explain what you're seeing, and text offers tips on technique.
Historical Hurricane Tracks : In an average year, six hurricanes blast across the Atlantic Ocean, Gulf of Mexico, and Caribbean, and two pummel the U.S. mainland. This site lets you chart the course of hurricanes and tropical storms that have blown up in the last 150 years.
National Oceanographic Data Center : More than a dozen databases hold measurements of the ocean going back to the 1960s, from wave height to plankton abundance. Try the Oceanographic Profile Database, which records variables such as salinity, temperature, pH, nitrate levels, and chlorophyll concentrations from samples taken around the world. A plankton storehouse holds data on total biomass and species abundances, with results from more than 140,000 tows. There are atlases on harmful algal blooms and the frigid Barents Sea, where the Gulf Stream peters out.
Archaeological Geophysics : Ground-penetrating radar is one of a slew of techniques that enable archaeologists to peer beneath the surface before they dig, pinpointing finds from single artifacts to entire villages.
Gouldiana
Biography: Stephen Jay Gould : An Interview with Steve Gould (voice)
The Spandrels of San Marco and the Panglossian Paradigm : A Critique of the Adaptationist Programme by Steve Gould and Richard C. Lewontin. An adaptationist programme has dominated evolutionary thought in England and the United States during the past forty years.
Love Him or Hate Him, Stephen Jay Gould Made a Difference : by Barry A. Palevitz in The Scientist.
The Structure of Evolutionary Theory : Reviewed by Richard Monastersky. Only Stephen J. Gould would dare to rewrite Darwin. But will America's best-known scientist leave much of an imprint?
Health
Microbes: What They Do and How Antibiotics Change Them : by Maura J. Meade-Callahan. Antibiotics and antibacterials do more damage than good because they:
Kill good bacteria inside the human body
Destroy microbes that clean up pollution
Lead to antibiotic resistance in microorganisms
Make treatment of some diseases difficult when overused
HIV–AIDS Information : For the latest on AIDS vaccines, treatments, and research, try this newly revamped information clearinghouse from the U.S. Department of Health and Human Services.
Pathoecology of Enterobiasis in the Prehistoric Southwest USA : The evolution of the human pinworm, Enterobius vermicularis, was influenced by hominid behavior and morphology. As a result, pinworms became the most tightly co-evolved parasite of humans and evolved an aerosol mode of infection unique among helminths. Successful infection mechanisms evolved over many millenia of human-parasite association and operate in different ways.
Human Evolution
Footsteps Through Time : This is an exhibit of the Museum of Man in Balboa Park in San Diego. It is sending kits to all public middle schools in the county to help teachers meet California science curriculum teaching standards. The materials were developed in conjunction with the museum's exhibit, documenting four million years of human evolution.
Mitochondrial DNA Clarifies Human Evolution : by Max Ingman. Recent DNA studies of several populations suggest that modern humans:
Originated in Africa
Appeared in one founding population
Evolved around 170,000 years ago
Migrated to other parts of the world to replace other hominids
Origins of Modern Humans: Multiregional or Out of Africa : by Donald Johanson. There are two theories about the origin of modern humans: 1) they arose in one place -- Africa and 2) pre-modern humans migrated from Africa to become modern humans in other parts of the world. Most evidence points to the first theory because: Fossils of modern-like humans are found in Africa. Stone tools and other artifacts support African origin. DNA studies suggest a founding population in Africa.
Comparative Sequencing Illuminates Vertebrate Evolution : To understand how humans came to be, science needs to consult the lesser beasts, particularly their DNA, for genomes carry the ultimate fossils, the living records of shared ancestries, written in a four-letter alphabet.
have paleontologists discovered why these creatures were so successful.
DNA from the Beginning : DNA from the Beginning is organized around key concepts. The science behind each concept is explained by: animation, image gallery, video interviews, problem, biographies, and links. It is available online (requires a Flash player) or in a set of CD-ROMs.
Maths
[ No additions this period ]
Paleontology
Nonavian Feathers in a Late Triassic Archosaur (Longisquama insignis) : Terry D. Jones et al., Science 288 (5474):2202-2205 (2000).
Modern Feathers on Chinese Dino : A new dinosaur fossil, found in north-eastern China, could change the way we think of dinosaurs forever. Writing in the journal Nature, palaeontologists from China and the United States suggest dinosaurs may have looked more like odd-shaped, large birds than huge, scaly lizards.
Rulers of the Jurassic Seas : Fish-shaped reptiles called ichthyosaurs reigned over the oceans for as long as dinosaurs roamed the land, but only recently
Paleozoic Prolecanitid Genera : Includes a graphic which illustrates their distribution based on biostratigraphic data from Russia, Germany, Canada, the USA, England, and elsewhere.
Foraminifera – A Complete Fossil Record : Unknown to Darwin, continuous sedimentation occurs in the open ocean, especially on aseismic ridges and plateaux. These areas experience a continuous rain of particles to the sea bed, and are among the most geologically quiescent places on Earth. A good example of this is a site on the Ceara Rise of the western equatorial Atlantic. As far as we can tell from biostratigraphy, this site has been sedimenting continuously for about 60 million years. Regular and gradual changes in the Earth's orbit affect the chemical composition of sediments which allows us to prove that there are no significant gaps in the record for the last 14 million years.
A Missing Page of Foram Information
Mummified Dinosaur Discovered In Montana : Leonardo, a mummified, 77-million-year-old duck-billed dinosaur was only about three or four years old when he died. His fossilized skeleton is covered in soft tissue – skin, scales, muscle, foot pads – and even his last meal is in his stomach.
Photos
Global Warming Photography : Aims to make climate change real and immediate by documenting effects we can see and measure today. The site provides examples of environmental shifts that range from disappearing toads in Costa Rica to melting permafrost in Alaska to surging sea levels in Siberia.
National Image Library : Looking for a winning shot of a copperhead, an ocelot, or a bald eagle to pep up a talk or add panache to a paper? You can download a plethora of free medium- and high-resolution photos of vertebrates, invertebrates, plants, and landscapes, mainly from North America.
Physics
MIT CourseWare in Physics : Electricity and Magnetism.
Recording Technology History : Follow the rise and fall of recording technologies with this timeline. It tracks developments in audio and video from Thomas Edison's first recording of human speech in 1877 to today's giant-screen IMAX films and desktop film editing. The pages brim with photos, explanatory diagrams, contemporary articles and sound files of early recordings.
The Linus Pauling Papers
Physics.org Webguide : This is a guide to Web sites useful for experts and novices alike. The site asks you to type in a question and indicate your level of physics know-how; it then provides an annotated list of sites.
Metals, Ceramics, Polymers, Composites : The nonstick coating Teflon has saved many hours of scrubbing pots, and you'll also find it in stents that prop open narrowed blood vessels. For more on Teflon and similar innovations, check out the A to Z of Materials.
Mathematical Constants : Mathematical constants – numbers such as p and e – are more than just strings of digits. They characterize the structure of mathematics, and this site describes the derivation of more than 100 common and obscure constants.
The Science of Spectroscopy : This is a site designed to teach undergraduates about the use of light in chemical analysis. It begins with an introduction to light and its properties and builds toward applications of spectroscopy in consumer products, medicine, and space science.
Reference Works
Calculators On-Line : You can calculate the estimated running speed of an extinct brontosaurus or figuring out the expected due date of a pregnant Nigerian dwarf goat. With over 16,495 calculators you can easily convert grams to moles or degrees Fahrenheit to degrees Celsius.
GeoData : Need to know how much water each American county consumes, or locate Cretaceous sedimentary deposits that might conceal a Tyrannosaurus rex skeleton? Check out this site at USGS.
Atlas of Cyberspaces : These Cybermaps help to visualise the digital landscapes beyond our computer screen, in the global communications networks and vast online resources. Like maps of the real world, they help navigate information landscapes, as well as being objects of aesthetic interest.
Ring Species
Ring Species as Bridges Between Microevolution and Speciation : .pdf file Contemporary microevolution: rate, pattern and process.
Species Variation and Diversity : Discusses (with photos) analagous and homologous evolution, cryptic coloration and species diversity in polyclad flatworms, a taxon with an incredible diversity in tropical waters.
Salamander Feeding Movies : This website gives a sampling of the diverse feeding strategies used by salamanders. Feeding in salamanders is usually completed in only a small fraction of a second. The movies on this site were made using high-speed video cameras running at up to 1000 pictures per second. Movies require a QuickTime plugin.
Feeding in Ensatina eschscholtzii
Rapid Evolution of a Geographic Cline in Size in an Introduced Fly : Raymond B. Huey et al., Science 287 (5451):308-309 (2000). The introduction and rapid spread of Drosophila subobscura in the New World two decades ago provide an opportunity to determine the predictability and rate of evolution of a geographic cline. In ancestral Old World populations, wing length increases clinally with latitude. In North American populations, no wing length cline was detected one decade after the introduction. After two decades, however, a cline has evolved and largely converged on the ancestral cline. Read online by subscription or see at your local library.
Ring Species: Salamanders : PBS explains Ring Species. This is their Map for Ensatina
Sociobiology
[ No additions this period ]
Speciation and Transitionals
Ecology & Evolution: Macroevolution : Gives many brief examples, with photos and graphics, for several forms of speciation.
Plant Evolution and Speciation Lectures : Speciation Models and Pathways. Deals mainly with plants, outlining important known elements in speciation processes.
Species Concepts : An outline that provides many definitions, with links to numerous topics.
Divergence of Icelandic Threespine Stickleback : .pdf file Gasterosteus aculeatus in two bottom types in lakes and a recently formed lagoon. This is a MS Thesis by B. Kristjansson (2001).
Rapid Evolution of Reproductive Isolation in the Wild : Evidence from Introduced Salmon. By Andrew P. Hendry et al., Science 290 (5491):516-518 (2000). Read online by subscription or see at your local library.
The Rapid Origin of Reproductive Isolation in Fruit Flies : by Nick Barton. Science 290 (5491):462-463 (2000). Read online by subscription or see at your local library.
Natural Selection and the Reinforcement of Mate Recognition : Megan Higgie et al., Science 290 (5491):519-521 (2000). Drosophila serrata and D. birchii have different but overlapping distributions and habitat associations along the east coast of Australia. The two species are sexually isolated by pheromones composed of cuticular hydrocarbons and hybrids are viable and fertile. Reproductive character displacement evolved within nine generations, indicating that there was strong selection on mate recognition. Read online by subscription or see at your local library.
Divergence in Seahorses : The typical generalized pipefish, Syngnathus spp., weaves its way through seagrass meadows or similar habitats propelled by a small tail. On the other hand the seahorses of the genus Hippocampus are more apt to hold on to some structure with a prehensile tail. When they have to swim they do so by fluttering an enlarged dorsal fin. The two genera are so separate one might wonder why they do not have their own families. The answer is the pipehorse, Acentronura dendritica, perhaps the best example of an extant intermediate species in the ocean. The tail is prehensile but still has a caudal fin and the dorsal is only a slight bit larger than those of the pipefish.
Scientists Uncover Secrets Of Feather Formation : Jurassic chicken project suggests that the barbs form first and later fuse to form a rachis, much like downy feathers are formed before flight feathers. Under the general rule of ontogeny repeating phylogeny, downy feather made only of barbs probably appeared before the evolution of feathers with rachides and capable of flight.
Species and Speciation : The is a very nice website, especially if you are interested in birds. The library of essays covers a wealth of topics in natural history and evolution.
Superspecies : Gives a list of somewhat more than 100 species that are now considered members of 53 superspecies of North American birds. Not listed are numerous cases where North American species are members of superspecies whose other members breed only outside of our area.
Sibling Species : Empidonax flycatchers, especially species such as the Dusky and Gray Flycatchers, are notoriously difficult to identify. In general, birds of this group are more readily separated by their songs than by their appearance; indeed, it is suspected that even the birds depend heavily on song to sort out who is who in order to avoid hybridizing.
Sibling Species in Flies : Bactrocera tryoni (right in photo) and B. neohumeralis (left) are sibling species of tephritid fruit fly. The species are sympatric: the Australian range of B. neohum-eralis is contained entirely within the greater range of B. tryoni. The species are identified by their mating time and the colour of their humerali calli.
Genetic Evidence for a Sibling Species of Heliconius charithonia : .pdf file By Chris Jiggins, Biological Journal of the Linnean Society 64:57-67 (1998). Molecular biology now permit us to examine cryptic species and see the real differences in their genes. The genes tell us the degrees of relationships and permit accurate production of cladistic trees.
Reproductive Isolation in Mouse Lemurs : .pdf file Molecular Evidence of Reproductive Isolation in Sympatric Sibling Species of Mouse Lemurs, by A. Yoder et al., International Journal of Primatology. Microcebus murinus and M. griseorufus.
Sibling species of Treecreepers : Sibling species are closely-related species that are nearly indistinguishable. The Short-toed Treecreeper Certhia brachydactyla differs subtly from the Common Treecreeper C. familiaris in a number of minor characters, including wing pattern and size of the hind toe. Behavioural patterns and ecology are quite distinct in these birds.
Interspecific Territoriality –Reproductive Isolating Mechanisms : Most birds defend their territories only against members of the same species; some, however, defend against individuals of other species as well. Generally such interspecific territoriality occurs between species that are very similar – as might be expected if territoriality is a way of guarding resources or mates.
Hybridization : When two populations of distinct but closely related birds come into contact, members of those populations may mate with each other and successfully reproduce. That process of hybridization creates problems for taxonomists, but is one sign of the continuous nature of the process of speciation – the evolutionary formation of new kinds of organisms.
Great Plains Hybrid Birds: These closely related pairs of species had evolved in isolation from each other, and bringing them into contact resulted in hybridization (interbreeding) between members of most of these pairs of congeners (members of the same genus).
Eastern Form
Eastern Screech-Owl
Yellow-shafted Flicker
Red-bellied Woodpecker
Great Crested Flycatcher
Eastern Wood-Pewee
Blue Jay
Tufted Titmouse
Eastern Bluebird
Rose-breasted Grosbeak
Indigo Bunting
Rufous-sided Towhee
Eastern Meadowlark
Baltimore Oriole
|
Western Form
Western Screech-Owl
Red-shafted Flicker
Golden-fronted Woodpecker
Ash-throated Flycatcher
Western Wood-Pewee
Steller's Jay
Black-crested Titmouse
Mountain Bluebird
Black-headed Grosbeak
Lazuli Bunting
Spotted Towhee
Western Meadowlark
Bullock's Oriole
|
Equid Evolution: A very nice family tree. There is also a page on Equid Biogeography with a tree showing geographic origins, speciation and extinction.
Haplochromis Radiation : These closely-related Cichlid fish species have evolved radically different feeding apparatuses in only a few thousand years.
Cichlid Room Companion : A recent study by Thomas Johnson of the University of Minnesota emphasizes just how remarkable cichlids are. Lake Victoria was bone dry roughly 12,400 years ago, yet hundreds of cichlids have evolved a species swarm there.
Spalax Chromosomal Races: Speciation can occur due to differentiation in chromosomes. Chromosomal races of Nannospalax ehrenbergei, the Israeli Mole Rat, are described here.
At the Water's Edge: Fish with fingers, whales with legs, and how life came ashore but then went back to sea. In this book science journalist Carl Zimmer brings his reportorial skills and impressive literary talents to bear upon one of evolution's most important questions. He presents an exquisite, up to date, narrative on the evolution of tetrapods, emerging from the water as amphibians, continuing to evolve into reptiles, birds and mammals, and then returning to the sea as mammalian cetaceans. Included in the story are fossil discoveries of the last 25 years – the finding of whales that walked on land and their gradual change to creatures of the deep sea, and the closing of the infamous time of absence known as Romer's Gap. This is a stunning narrative.
Species, Speciation, and the Environment : by Niles Eldredge. The environment plays a major role in the evolution of species when:
Dramatic environmental changes trigger extinction as well as speciation.
Species arise when isolated populations acquire new adaptations to a changing environment.
Species stabilize for millions of years but go extinct when their ecosystem is disrupted.
Evidence of Evolutionary Transitions : by Michael Benton.All living organisms share the same family tree. This fact is backed by evidence such as:
Archaeopteryx, a missing link between reptiles and birds.
Mammalian hearing structure, which evolved from reptilian jawbones.
The animals of the Galapagos, isolated from the rest of the world.
DNA profiles of life forms, present and past.
Speciation and Biodiversity Interview with Edward O. Wilson : The formation of new species can happen relatively quickly; however it cannot keep up with the current extinction rate.
Species require energy, stability, and enough space -- all of which are decreasing.
Some populations are no longer healthy because there are too few individuals.
In one human lifetime, half the world's species will disappear if the rate continues.
A Missing Page of Foram Information
Hippopotamuses are the Closest Extant Relatives of Whales : by M. Nikaido et al., Proc. Natl. Acad. Sci. 96 (18):10261-10266 (1999). Insertion analysis of short and long interspersed elements is a powerful method for phylogenetic inference. In a previous study it was found that cetaceans, hippopotamuses, and ruminants form a monophyletic group. We now have isolated and characterized 10 additional loci, thereby shedding light on the origin of whales.
Retroposon Analysis of Major Cetacean Lineages : by M. Nikaido et al., Proc. Natl. Acad. Sci. 98 (13):7384-7389 (2001). We demonstrate that: (i) Odontocetes are monophyletic; (ii) Ganges River dolphins, beaked whales, and ocean dolphins diverged (in this order) after sperm whales; (iii) three other river dolphin taxa, namely the Amazon, La Plata, and Yangtze river dolphins, form a monophyletic group with Yangtze River dolphins being the most basal; and (iv) the rapid radiation of extant cetacean lineages occurred some 28-33 million years B.P., in strong accord with the fossil record. (Be sure to see the colorful cladogram showing the evolutionary relationships between living whales and dolphins and the order of descent.)
Molecular and Morphological Supertrees for Eutherian (Placental) Mammals : by R. Liu et al., Science 291 (5509):1786-1789 (2001). At and below the ordinal level, the molecular and morphological supertrees both largely recovered the same interfamilial taxa. Of five exceptions at these hierarchical levels, three coincided with the recent challenges from molecular sources for the non-monophyly of Artiodactyla, Insectivora, and Microchiroptera. In contrast to the combined and morphological analyses, the molecular supertree favored a deep nesting of Cetacea within Artiodactyla and its close relationship to Ancodonta. This alternative arrangement was also obtained by the combined data when weighted 8:1 in favor of phylogenetic syntheses that largely emphasized multiple genes. See online by subscription or at your local library.
The Ancestry of Whales : .pdf file. by K. D. Rose. Science 293 (5538): 2216-2217 (2001). We are rapidly filling the gaps in the cetacean transition from land to water. Two other evolutionary transitions vital to our understanding of the relationship between whales and artiodactyls beg for elucidation: the precise ancestry of hippopotami and the origin of artiodactyls themselves. The answers seem likely to come only from an improved fossil record –perhaps from the same region that has yielded fossils showing that whales evolved from artiodactyls.
Divergence of Bee-eaters : Ancestral populations differentiated as a result of having been isolated in rain forest between northern and southern tropical savanna. Carmine Bee-eaters (M. nubicus) and Southern Carmine Bee-eaters (M. nubicoides) are believed to have diverged from a common ancestor only about 13,000 years ago.
Persistence of Neutral Polymorphisms in Lake Victoria Cichlid Fish : by S. Nagl et al., Proc. Natl. Acad. Sci. 95 (24): 14238-14243 (1998). The young age of the Lake Victoria haplochromines is supported by molecular studies of mtDNA, the major histocompatibility complex (Mhc) genes, and other genetic markers. The mtDNA studies also suggest that Lake Victoria haplochromines may be monophyletic. The founders of the flock may have come from the rivers in the Lake Victoria basin, in which their descendants may still live. The recency of speciation makes the Lake Victoria haplochromines a suitable model for testing the predicted persistence of neutral polymorphisms through the speciation phase. The present study has been designed to test this prediction.
Taxonomy
Taxonomy and Nomenclature : Taxonomy (sometimes called systematics) is the science of classifying organisms. The Linnean system of classification, used for both plants and animals, was developed more than two centuries ago by the Swedish botanist Carolus Linnaeus (Carl von Linné). It is a hierarchical system – that is, each organism belongs to a series of ranked taxonomic categories, such as a subspecies, species, genus, family, etc. See Linnaeus and Primates for more about him.
Ways of Classifying Life : One of the earliest and critical concerns of any science is development of a comprehensive and clear classification system for its object of study. For biogeographers and other life scientists, there are several systems of classifying living things, depending on their purposes.
Biogeography and Systematics : This is a very good introduction to taxonomy and systematics and the use of cladistic analyses to determine the proper relationships between species. The illustration given to aid understanding of genetic code comparisons may be particularly useful.
Universe
MIT CourseWare in Astronomy : Hands-On Astronomy: Observing Stars and Planets.
Space Station Overhead : Want to see the International Space Station go past your locality? Select a city from the list provided or use an applet which will allow you to enter your exact location.
Planetary Nomenclature : With thousands of valleys, prominences, mountains, and plains in our solar system, you can get ensnared in terminology. This site lists official names and locations of mountains, craters, and other surface features on our neighboring planets and their moons.
Northern Lights : This site delves into aurora science at a generally accessible level. A question-and-answer section encourages students to use the site for classroom projects, and a monthly photography contest targets those in pursuit of the aurora's artistic side.
Big Bang Nucleosynthesis : Gamow, Alpher and Herman proposed the hot Big Bang as a means to produce all of the elements. Now we know that two processes occur: most helium is produced in the Big Bang but carbon and everything heavier is produced in stars. Most lithium and beryllium is produced by cosmic ray collisions breaking up some of the carbon produced in stars.
Ned Wright's Cosmology Tutorial : Cosmology is the study of the origin, current state, and future of our Universe. This field has been revolutionized by many discoveries made during the past century. This tutorial is an attempt to summarize those discoveries.
Formation of the Elements : In the beginning.... Well, what we're calling the beginning here is the universe when it had a temperature of 100,000,000,000 K. The universe had already existed for a very small fraction of a second. The universe was dominated by radiation. There was some matter present, but it was minuscule compared to the amount of radiation.
Astronomy Picture of the Day : Fantastic daily photos from NASA with links to more information on subjects.
Expanding Universe : This is one of the most amazing discoveries of the 20th century. All galaxies in the universe (beyond our neighbors like Andromeda) are moving away from us. The velocity of their recession is proportional to their distance.
Astrogeology Research Program : Smothering dust storms on Mars, pristine impact craters on Venus, possible liquid water on Jupiter's moon Europa -- Earth isn't the only place that piques the interest of geologists. Dig into the geology of the planets, moons, and asteroids in our galactic neighborhood.
Origin of the Universe, Earth, and Life : The term evolution usually refers to the biological evolution of living things. But the processes by which planets, stars and galaxies form and change over time are also types of evolution. In all of these cases there is change over time, although the processes involved are quite different.
Zoology
The Avian Leg : The bird's leg has the typical vertebrate pattern of femur, tibia, and fibula. No, bird's legs to not bend the wrong way. That's the ankle that looks like an elevated knee. Bone by bone, compare the avian and mammalian legs, starting from the hip joint and working downward. Check out Avian Skeletal Adaptations and these Fish-Bird-Cat-Dog Comparisons. Then you might Click on the Bird Skeleton. The study and reconstruction of the chicken skeleton is very interesting, inexpensive, and down right tasty. And this illustration shows that Even Dino Legs are Like Chickens' and Our's. Finally Avian Anatomy and Morphology will help you discover how many aspects of birds have evolved to better fit them for conditions of life and flight.
The Penguin Page : There are 16 species of penguins in the world. They inhabit the coastal regions of the southern hemisphere and do not normally extend their ranges above the equator. Please click on one of the six genera in the above imagemap to find more information on member species.
Toxic & Harmful Algal Blooms : The dainty dinoflagellate Karenia brevis is a marine alga, which can contaminate fish and shellfish, exuding a potent toxin that can cause diarrhea and vomiting. Find out more about the five main kinds of algal poisoning in U.S. waters at this site.
Protist Information Server : The Protist Information Server swarms with photos of more than 1600 species of protists, a diverse group of often one-celled eukaryotes that include protozoans, slime molds, and the malaria parasites. Search the 29,000 images in the gallery by taxonomic group.
Merck Veterinary Manual : Although the newly released version of this standard reference doesn't cover all creatures great and small, it does run down many of the diseases and conditions that can strike a variety of research animals, from turtles to fish to monkeys. The free text also amasses a wealth of information on hygiene, nutrition, and disease prevention.
Diseases of Wildlife : This is a wildlife biologists' version of the CDC. The USGS keeps tabs on diseases that strike wild animals, probes their causes, and helps wildlife managers fight epidemics. The site is a clearinghouse of information on animal illnesses with backgrounders on the epidemiology of chronic wasting disease similar to mad cow disease that has killed deer and elk in 10 states, as well as the infamous West Nile virus. The nasty bug rarely infects humans but has attacked more than 200 species of birds and wild mammals since arriving in the United States.
Marine Flatworms of the World : Beautiful worm might sound like an oxymoron – until you see the Technicolor creatures on display at this site. They live in warm seas, and some of them can grow to the size of a dinner plate. Taxonomy pages give a genus-by-genus breakdown of the group. Learn about their anatomy, mating habits (most are hermaphrodites), diet and defenses. See the photo gallery packed with underwater shots of Day-Glo worms.
Cichlid Room Companion : A recent study by Thomas Johnson of the University of Minnesota emphasizes just how remarkable cichlids are. Lake Victoria was bone dry roughly 12,400 years ago, yet hundreds of cichlids have evolved a species swarm there.
The Feathers Of Dinosaurs : The appendeges on these dinosaurs are NOT collagenous dermal or musculoskeletal structures. They are clearly preserved as external integumental structures. Feathers and scales are both made of keratin. As with reptilian scales, feathers begin their development from a follicle. A single point mutation will change the scales of a chicken into feathers.
Tool Use in New Caledonian Crows : In the wild, the crows make a wide variety of tools from a number of different materials, and they will also readily do so in captivity, even with unfamiliar materials.
Crinoids : The popular names for crinoids are sea lilies (for fixed crinoids) and feather stars (for free-swimming crinoids). Crinoids belong to the Echinoderms which also includes Echinoids (sea urchins) and starfish.
Phylogeny of Turtles : In addition to the nicely illustrated cladogram, a slide show based upon a 1996 article in Natural History magazine, and other documentation about turtles, makes this site attractive and informative.
Whales -- Land-to-Sea Transitional Series : It took less than 15 million years for the whale lineage to move from land, through shallow bays and coastal waters, to deep marine environments. By 40 million years ago whales had become essentially the animals we know today.
Dinos-to-Birds Transitional Series : Dinosaur and avian taxonomy has benefited immensely from extremely detailed fossils found in fine sandstones of the Liaoning province of China. A cladogram shows the evolutionary relationships within the Theropod Dinosaurs which, along with the Sauropod and Ornithischian Dinosaurs, make up the great class of Earth's dominant animals that went extinct 65 million years ago.
Birds of Stanford : This is a wonderful website with a large collection of essays on most aspects of avian biology. The species treatments and essays are from The Birder's Handbook by Paul Ehrlich, David Dobkin, and Darryl Wheye (1988). Also a nice site guide to birding in the Stanford camopus area.
Introduction to Monotremata : The order Monotremata is a fairly ancient mammalian taxon. It includes two families, Ornithorhynchidae (Platypus) and Tachyglossidae (Echidnas). Although considered mammals, monotremes have several characteristics not generally considered mammalian.
Darwin's Finches: Phylogenetic Relationships : Evolution: Vol. 56, No. 6, pp. 1240–1252. Darwin's finches are part of a well-supported monophyletic group of species, all of which build a domed nest. All but two of the non-Darwin's finches included in this clade occur on Caribbean islands and most are Caribbean endemics.
Asilidae: Robber Flies : Like tiny hawks, they swoop down on unwary insects or spiders, carting off a meal and sucking it dry. The site swarms with information on the biology of nearly 7000 species of robber flies.
WhaleNet : Aimed at secondary school students and teachers, to spark interest in science and the environment. Students work with real data and try out some of the tasks cetacean biologists have to master, such as identifying individual humpback whales from pigmentation and notches on the tail fin.
Discover Chimpanzees : Tells the life stories of the Gombe chimps through photos, comments from researchers, and video capturing the primates' repertoire of behaviors.
Hypomyces : This site delves into the lives of this genus of fungus-eating fungi, profiling the 30 most common species in temperate climates. Brief accounts describe their ecology and involved life cycles.
Chimpanzee Cultures : Chimps of the Ivory Coast invented a nutcracker. They position a nut on a stone anvil and bash it with a stick or rock. In Tanzania, they haven't figured out the anvil trick, but they use crumpled leaves to sop up tasty ants. This site documents regional differences in behavior.
Sea Urchin Embryology : Spiky and rotund, an adult sea urchin looks more like a big, wet cocklebur than one of our close kin. Yet the early stages of development are very similar in humans and urchins, which makes these marine echinoderms excellent subjects for labs on embryology.
Wolbachia : This genus of bacteria infests up to 75% of the world's insect species and invades other invertebrates as well. Although they're usually peaceful guests, the ingrates sometimes slay their hosts, a feat that makes them promising biocontrol candidates.
Caterpillar Host Plants : Learn what's on the menu for some 22,000 moth and butterfly species at this collection of caterpillar dietary data from the Natural History Museum in London.
Virtual Dissection of a Frog :
Visitors to Froguts can dissect a frog without catching even a whiff of formaldehyde. Ten easy-to-follow explorations meld computer graphics and photos of real dissections.
Crustacea: The Crayfish : The site reviews the taxonomy of the three known families and provides species checklists for all 50 states and for the more than 30 other countries with native forms.
North American Mammalian Paleofaunal Database : What information about the distribution of fossils in North America. You will need to known the Latin name of the mammal. Knowing the geologic age will help.
Molecular Evolution of the Dog Family : The morphological diversity of 34 species is matched by the diversity of their natural history. Canids inhabit temperate and tropical forests, savanna, tundra and deserts.
Cannes of Worms : Caenorhabditis elegans is a favorite for probing embryonic development. These movies capture worms slithering, mating, and slurping their dinner, but most focus on how the nematode takes shape.
Moths of North America : Entomologist Paul Opler of the U.S.G.S. curates the still-growing guide and helps run a parallel site on butterflies. Among the handy moth resources are county-by-county range maps, species checklists for the lower 48 states of the United States, and distribution data for northern Mexico.
Social Insects : Looking for information on ant habits, taxonomy, anatomy, distribution, and conservation? Visit Antbase to find among the eight databases a gallery teeming with more than 800 ant images, including representatives from 60% of the world's subfamilies.
|