Introduction
This series of pages is designed to expand your knowledge and interest in the biology of organisms and their evolutionary history. Increasingly, as biology departments expand their curricula toward cellular and molecular biology and genetics, the biology of organisms gets short-changed. Certainly there are exciting, fundamental, and money-making advances in cellular and molecular biology, but that does not mean that organismal biology is stagnant or uninteresting.
This set of links was originally associated with a course called Paleobiology, taught in the Department of Geology at the University of California, Davis. There is no academic break between biology and paleobiology, so I have felt it was both appropriate and necessary to include a lot of information that has been gathered from living organisms.
This is very much a work in progress, and I make no apologies for shortcomings. If you find portions you don't like, let me know, and tell me how you think I should improve them.
Some of these Web pages are only accessible from a UC Davis E-address: in other words, they won't work from your non-University address. You might have to go to the library!@!
Studying Evolution
Mini-Essays and Sub-sections
How Evolution Works
Scattered through this section I'm also placing some journal references to short pieces on the principles of evolution. Many of them are from Current Biology. This journal is not general access, and I try not to use such journals. However, most major universities probably have an E-subscription to it. Otherwise you might have to go to the library (horrors!).
Conway Morris, S. 2006. Evolutionary convergence. Current Biology 16: R826-827.
Erwin, D. H. 2006. Evolutionary contingency. Current Biology 16, R825-826.
Sniegowski, P.D., and H. A. Murphy. 2006. Evolvability. Current Biology 16: R381-384.
How Fast Can Evolution Be?
-
Bacteria evolve immunity to antibiotics astonishingly fast Blog by Carl Zimmer about a new paper, November 2005.
-
Very fast evolution among Australian rainforest frogs. Press release, UC Berkeley, October 2005. The paper was in Nature.
-
Perhaps the most astonishing examples among vertebrates are the cichlids of African lakes, especially Lake Victoria and Lake Malawi:
-
Rapid evolution between American finch populations. National Geographic News, January 2002.
-
Under intense fishing pressure, northern cod were evolving very rapidly toward faster maturation when the populations collapsed. Olsen, E. M., et al. 2004. Maturation trends indicative of rapid evolution preceded the collapse of northern cod. Nature 428: 932-935; and comment, p. 899-900. (This won't be freely available on the Web.]
-
New research published in Science. This is not the formation of new species (yet), but it suggests that in some circumstances, incipient species can evolve in a geological eye-blink. The papers in Science: start from this summary
-
A sub-fossil example: The mini-radiation of geese on prehistoric Hawaii. National Geographic News, February 6, 2002. What's more, they were all descended from the Canada goose, within the last half-million years.
-
Almost all the examples above are from vertebrates. But very fast evolution has now been documented from insects. A new example (January 2005), the fastest-evolving arthropod so far studied, is a group of Hawaiian crickets (that's right, NOT fruitflies). The paper is Mendelson, T. C., and K. L. Shaw. 2005. Rapid speciation in an arthropod. Nature 433: 375376. Nature does not make its papers generally available on the Web.
The Economics of Evolution
You would predict that organisms would evolve to save as much resources as possible: food, stored energy (tissues, chemicals), energy, etc.. And many times they do. However, we can all think of machines that "waste" energy yet are very successful: military jet fighters, over-engined sports cars, and so on. So dramatically energy-consuming organisms might be selected for in some circumstances. I'm going to list here some cases where simple economic factors may have molded the evolution of the organism concerned.
The Game Theory of Evolution
-
Is sex really necessary? The usual thought is that in complex organisms at least (plants and animals), sexual reproduction is needed at least some of the time. Life's too short to fully discuss that point here. What is interesting is that there seem to be some animals (the bdelloid rotifers) that have had no sex for forty million years Article from Science News, May 20, 2000.
And, by the way, Too much sex is bad news if you are a Soay ram. The Scientist news service, February 2001. LINK BROKEN: THEY WANT MONEY NOW
-
Polygamy is fairly common in nature: but why would polyandry evolve? (One female, several males). National Geographic feature, February 2005.
Pfeiffer, T., and M. A. Nowak. 2006. Digital cows grazing on digital grounds. Current Biology 16: R946-949. [Evolution, cheating, and the Internet.]
Sexual Reproduction and Mate Choice
I don't feel that I'm obsessed with sex: but there are some wonderful examples of natural selection and evolution here!
-
Bowerbirds
-
Feathers of Seduction. National Geographic feature on birds of paradise, July 2007.
-
Why are male ptarmigans so scruffy? An account of the research project, originally published in Natural History.
-
Why ptarmigan get scruffy. Abstract of the paper, 2001.
-
Monogamy: is it the result of a freak mutation? No, but this is an interesting story: Los Angeles Times story reprinted in the San Francisco Chronicle, 2004. (The LA Times takes its stories off the Web quickly.) One species of meadow vole is monogamous, the rest are not. In this case at least, it seems to have resulted from a one-gene mutation. Obviously, both systems work.
-
Baboon butts: the large red swellings on the butt of a female baboon really are truthful advertisements about her health and value as a mate. Other version of the story:
-
Harvard Crimson
-
Sex games among fishes. Press release, Purdue University, April 2001. Same press release here
-
The display of the red-bellied two-spotted goby. From the Science newsroom, October 2001. The same story is here
-
McClure, B. 2004. Pillow talk in plants. Nature 429: 249-250. [Mate choice in plants.]
-
The strange story of insect genitalia
-
Why do (some) fruit flies have monster sperm?
-
Pizzari, T. 2006. The paradox of sperm leviathans. Current Biology 16: R462-464.
-
Sexy stalk-eyed flies
-
Wimps, be encouraged (as long as you are a Tanzanian cockroach): females of this species prefer wimpy males to dominant bullies. .
-
MATING GIFTS
In many species the male entices the female to mate by bringing her gifts. In raptors, the male may bring a prey he has caught: this not only "pleases" the female, but shows her that he is a good hunter. The presentation of these "nuptial gifts" has been most studied in insects. Three cases are featured here. In the first, males are in the process of evolving cheating behavior about their gifts. This was exploited by the researchers, who provided the males in question with cotton balls to replace the nutritious balls of tufted seeds that they would otherwise have gathered one by one. (Diamonds vs. cubic zirconia...?] In the second two, the male provides the female with a chemical that protects her from spiders: the neat trick is that the chemical is in his sperm....
-
Material girls: a quick introduction to mating gifts and several choice examples. From California Wild magazine, Spring 2004.
-
Cheating by empidid dance flies:
-
Sexual Cannibalism
-
The case of the rattlebox moth:
Said the rattlebox moth to his date,
"If you fear a spidery fate,
My seminal injection
Gives lifelong protection:
Don't flutter around, be my mate!"
© RC 1999
Traumatic insemination This is pretty gruesome stuff.
-
Sexual behavior in humans:
When to sniff a lady's armpits. Look, I don't make this stuff up! This is science, after all.
Sperm Competition
Parental Conflict
The interests of males and females may not always be identical. This sets up the possibility of subtle warfare between the sexes, especially in matters of reproduction.
Coevolution: Symbiosis
Ants and plants
Ants and acacia plants
Mostly about the acacias, from Wayne's Word
Ants that grow gardens of fungus
Co-operation in hunting
December 7, 2006. Groupers and moray eels co-operate to hunt.
Squid and luminescent bacteria
Moran, N. A. 2006. Symbiosis. Current Biology 16, R866-871.
Coevolution: Plants and Pollinators
Specific plant/animal partnerships in pollination
-
Bats and plants
-
Carrion plants and carrion flies
-
Carrion flies pollinate "carrion plants", and the carrion plants are so called because they exude the stench of rotting flesh, thus attracting the flies that are adapted to home in on dead carcasses. A huge carrion plant, the titan arum, has had a lot of publicity recently: see these stories:
-
Figs and fig wasps
-
Yuccas and yucca moths
From Wayne's Word.
-
The senita moth and the senita cactus.
Terra Daily, August 16, 2007.
-
Cycads and thrips
-
National Geographic News
-
Terra Daily
- The paper was in Science, so will be freely available on the Web in early 2008: Terry, I. et al. 2007. Odor-mediated push-pull pollination in cycads. Science 318: 70.
-
Zamia, a cycad that is pollinated by beetles
-
Orchids and the sex lives of their pollinators
-
The relationship can be VERY sophisticated. Carl Zimmer, posted on the Web January 2004 at his Loom page on the Corante site. And there's a lot more good stuff posted there!
-
Cheaters
Some plants cheat: they attract bees to them, are pollinated, but don't give the bees anything good for them. (Hallucinogens or intoxicants, sometimes!). Orchids are experts at this. But there are other examples:
-
Explosive pollination
-
Pollinating plants that grow on the sides of tree trunks
-
The snow skink, the bee, and the honey richea of Tasmania The biological bodice-ripper: at least, that's what Jessa Netting of the Nature news service called it. Astonishing complexity in this relationship. Research published October 2000.
-
The New Zealand red mistletoe, and the tui and bellbirds that pollinate them so skilfully.
And why the whole system is in jeopardy. From Natural History, September 2000. One of the rare papers that Natural History has posted on its Web site.
This section updated December 6, 2006.
All links checked, September 28, 2007.
Coevolution: Plants and Seed Dispersal
Seed dispersal by non-biological agents
Explosive seed dispersal by the dwarf mistletoe.
Explosive spore dispersal by fungi
-
Spore launchers by Adam Summers in Natural History magazine, December 2005.
Seed dispersal by biological agents
Coevolution: Predators and Prey
-
Rodents and rattlesnakes.
-
Bats, moths, and echolocation. Great article by Sid Perkins in Science News, May 2005.
-
A suggestion that "bats invented butterflies", a short news report from BBC News OnLine, January, 2000. Some moths may have evolved into day-flying butterflies to avoid nocturnal bat predation. (No evidence for this, but it sounds plausible.)
-
Lizards and fireflies, from the New York Times, 27 July 1999.
-
Bass and whirligig beetles: research published in PNAS, October 2000: article in
Science News
-
Coatis and millipedes. There are millipedes in my garage that stink if I step on them. However, coatis love them like candy. This is how they get rid of the smelly defensive chemicals. Research by Paul Weldon and his team at the Smithsonian, published January 2006. For more, see this backgrounder on poisonous millipedes and look for the story about capuchin monkeys.
-
Evolutionary race between copepods and diatoms in the plankton. Nature news service won't let you look at their original piece, so try this one from the investigators. Eat me, and I'll sterilize you!.
-
How a pitcher plant lives only on termites. Nature news service removed it from open access, so try this alternative. The paper is Merbach, M. A. et al. 2002. Mass march of termites into the deadly trap. Nature 415: 36-37. From the authors
Coevolution: Herbivores and Plants
Coevolution: Mimicry
-
Batesian mimicry works: a case study with coral snakes and king snakes. New research, March 2001.
-
The mimicry of the blue-striped fangblenny can be turned on or off. The paper is Coté, I. M., and K. L. Cheney. 2005. Choosing when to be a cleaner-fish mimic. Nature 433: 211-212. January 2005. Animal Communication project site
-
MIMICRY WITHIN A SPECIES. Often mimicry occurs between species. What could be gained by mimicking one's own species? Here are two studies that give the same answer for two completely different animals.
-
If you were a small male of the giant Australian cuttlefish species Sepia apama, you wouldn't normally be able to compete with other males for mating. However, if you can mimic a female, you may be able to sneak into a group of females and mate with one of them: as long as the big resident male doesn't notice... The paper is Hanlon, R. T., et al. 1005. Transient sexual mimicry leads to fertilization. Nature 433: 212. January 2005. Nature doesn't make its papers freely available on the Web.
-
Mimicking the girls: good idea if you are a Canadian garter snake. Based on a paper in Nature: Shine, R., et al. 2001. Benefits of female mimicry in snakes. Nature 414: 267. Nature doesn't make its papers freely available on the Web. National Geographic News
Coevolution: Parasites
-
Parasite Rex. The first and most important link here is not a Web site. It's a book: Parasite Rex, by Carl Zimmer. It is one of the best science books I have ever read. Required reading by all evolutionary biologists, actually, by all biologists. Here's a review of it by Kevin Padian
-
The Parasite Files. This is an archive of some of Carl Zimmer's articles and blogs on parasites.
-
Do parasites rule the world?. Feature article by Carl Zimmer for Discover magazine, August 2000. Discover seems to have removed it, so I'm sending you to this alternative (text only). And here's another copy of the text.
-
The malaria parasite. The bite of a malaria-carrying mosquito makes a human more attractive to other mosquitoes: the perfect way for the parasite to be spread. Abstract of paper, September 2005.
-
Nest parasites. Cow-birds are "nest parasites": they lay their eggs in other birds' nests. Long feature article from Science News, May 1998.
-
The wasp and the spider: "Web of Death"
-
Sex and deceit: beetles that infiltrate bee colonies
-
Wolbachia What the parasite Wolbachia does to insects that it infects.
-
Toxoplasma
You've probably heard that Toxoplasma is a single-celled organisms that infects cats. And if you're pregnant, and you get toxoplasmosis from an infected cat, it can lead to a miscarriage if you are lucky and a deformed child if you are not. But how has Toxoplasma evolved for life in a cat? Well, here's one scary thing that it does: it alters the behavior of rats. That's right: rats, not cats.
Coevolution: Societies and Sociobiology
Altruism?
-
Arabian babblers. Science.
-
The nesting of goldeneye ducks. National Geographic News, December 2001. This news item doesn't stress the tremendous advantage gained by duck cheaters: for that, see the paper in Nature: Åhlund, M., and M. Andersson. 2001. Brood parasitism: female ducks can double their reproduction. Nature 414: 600-601.
-
It takes a mob to rear a meerkat. National Geographic News, September 2001.
-
West, S. A., et al. 2006. Altruism. Current Biology 16, R482-483.
Is evolution going on now in human populations?
The short answer is YES, OF COURSE!
Molecular Evolution
The Case of the Cambrian Explosion
The Case of the Cenozoic Mammal Radiation
Primate and Human Evolution
Bacteria
-
The largest bacteria ever discovered (1999):
The Senses: Sight, Smell, Hearing, and so on.
-
Frog pheromones. BBC News OnLine, Thursday, September 30, 1999
-
The sniff of a stomatopod. Article by Adam Summers, originally published in Natural History.
-
Evolving a sense of small in coconut crabs. Coconut crabs evolved to live in air, from marine ancestors. To make a living, it became important to evolve a sense of smell that would work in air, rather than in the water. The biggest arthropod in the world, the "robber crab" of Christmas Island in the Indian Ocean, half a meter long and weighing over 4 kg (9 lbs.), has evolved a sense of smell that is strikingly like that of insects (although they belong to very different arthropod groups, and evolved their sensors separately). And it's not for smelling coconuts: it's for smelling the rotting corpses that provide much of their diet. The paper is Stensmyr, M. C., et al. 2005. Insect-like olfactory adaptations in the terrestrial giant robber crab. Current Biology 15: 116-121. It may be available on the Web. January 2005.
-
The lobster's violin: a unique sound-producing mechanism. Article by Adam Summers, originally published in Natural History, June 2001.
-
Evolving sonar in bats: very early, probably along with their evolution of flight. Bats evolved flight and sonar together; later, fruit bats lost sonar as they came to specialize of fruit rather than insects. Bats seem to have had an early explosive evolution in the northern continents in Eocene times, and have been rather stable since.
-
Overview in Science News
-
The paper is Teeling, E. C., et al. 2005. A molecular phylogeny for bats illuminates biogeography and the fossil record. Science 307: 580-584, and comment, 527-528. Here is the abstract, with link to full text. Look also at a perspective published in June 2004: Fenton, B., and J. Ratcliff. 2004. Eavesdropping on bats. Nature 429: 612-613, to be even more impressed with bat signalling. Nature does not make its papers freely available on the Web.
-
Why do swordfishes have warm eyes? All the better to see with... The paper is Fritsches, K. A., et al. 2005. Warm eyes provide superior vision in swordfishes. Current Biology 15: 55-58. From PhysOrg.com, January 2005.
-
Birds can see ultraviolet. The paper is Dalton, R. 2004. True colours. Nature 428: 596-597. Nature does not make its papers freely available on the Web. Here is a PDF file of the paper, legally posted by the author.
-
The nose of the star-nosed mole. Article by Carl Zimmer, 2005.
-
Brittle stars that can see:
-
How do lobsters sniff for scents in water?. Press release, UC Berkeley, December 2001.
This section last updated September 28, 2005.
All links checked October 5, 2007.
Weird and wonderful things that have been selected for survival
-
Different ways to dig a hole to live in. Natural History Magazine, December 2006/January 2007.
-
What makes gecko feet sticky?
-
How do geckos keep their sticky feet clean?
-
The sucker-footed bat of Madagascar.
National Geographic News, January 2007
-
How do flies climb walls?
Shoe fly by Adam Summers in Natural History magazine, February 2006.
-
The chameleon's tongue. National Geographic News, May 2004.
-
The spitting cobra aims for your eyes. National Geographic News, February 2005.
-
How the archer fish learns to spit. American Scientist, May/June 2006
-
The strike of the mantis shrimp.
-
The bite of the trap-jaw ant. Their jaws spring shut with the fastest recorded speed of any predatory body part.
Adam Summers in Natural History, December 2006
-
The sting of the jellyfish. Jellyfish fire their stinging cells (nematocysts) with an acceleration over 1 MILLION g, on a nanosecond time scale. The impact (on an ultramicroscopic scale) is about like that of a bullet. The paper is Nüchter, T., et al. 2006. Nanosecond-scale kinetics of nematocyst discharge. Current Biology 16: R316-318. May 2006. Press release
-
How clever are crows?
-
Collecting water in a desert. Based on Parker, A. R., and C. R. Lawrence. 2001. Water capture by a desert beetle. Nature 414, 33-34.
-
The corkscrew duck and other stories. National Geographic News, October 2001.
-
The behavior of the Madagascan poison frog. Science News, April 2001.
-
The pitohui, the first poisonous bird ever discovered. Kate Wong in California Wild, 2005.
-
How blindsnakes eat lots of ants. Article by Adam Summers, originally published in Natural History, May 2002.
-
The fastest muscle of any vertebrate. The swimbladder muscles of the toadfish. But why? Press release from the University of Pennsylvania, October 2001.
-
How the puffer fish puffs itself up. Article by Adam Summers, originally published in Natural History, October 2001.
-
Penguin waddling. It's a lot more efficient than you'd think! Carl Zimmer article, March 2001.
-
Shark teeth. Adam Summers in Natural History, March 2006
-
Stingray jaws. If they are made only of cartilage, how can they bite hard enough to crush clams?
-
The amazing swimming ability of the boxfish By Adam Summers in Natural History magazine, October 2005.
-
Groupers and moray eels co-operate to hunt. New research, December 2006.
-
The python's stomach. Essay by Jared Diamond in Discover, April 1994.
-
A marsupial that breathes through its skin. From BBC News OnLine.
-
Sloths that adapted to life in the sea. Blog by Carl Zimmer, 2004.
-
How not to get frozen.
National Geographic News, March 2005.
-
Tick saliva hits the human immune system: a highly sophisticated way of stopping the target species interfering with your blood-sucking! ScienceNow, 2001
-
Dracula ants. Story from the New York Times, January 9, 2001.
-
How do ant colonies work?. Deborah Gordon's research on harvester ants
-
Porcupine quills. Natural History, March 2006
-
The defense of the bombardier beetle. San Francisco Chronicle, August 1999.
-
Beetle larvae that protect themselves with a coating of their own feces.
-
The golden bug and its eggs. Originally published in Natural History, March 2002.
-
Bees that kill their enemies by cooking them. Science News, September 2005.
-
Jumping nematodes. Article by Adam Summers, originally published in Natural History, March 2002.
-
Warm-blooded plants. From Science News, December 2003.
-
The dance of the daffodil. Article by Adam Summers, originally published in Natural History, April 2002.
-
How a Venus fly trap works.
-
Explosive pollination in the bunchberry dogwood. Live Science , 12 May 2005.
-
How the sacred lotus stays so clean. Adam Summers in Natural History, April 2006
-
The Jamaican bromeliad crab, which lives in trees
Bioluminescence in the Dark
This section last updated January 9, 2007.
All links checked, October 5, 2007
Ecology and Paleoecology
[Return to Geology Department Home Page]
