Favorite Examples of Evolution

When the cold bites, When the review stings, When the news is sad, I simply remember these evolving things, And then I don’t feel so bad! — with apologies to Rodgers and Hammerstein

Over on Twitter, the biology students from George Jenkins High School in Lakeland, Florida, asked me and many others: “What’s your favorite example of evolution?”  There are so many fascinating examples that it’s hard for me to pick just one. So, here are half a dozen examples that are among my favorites.

  • The discovery by Neil Shubin and colleagues of Tiktaalik, an extinct fish (pictured below) from the Devonian that was poised to give rise to terrestrial vertebrates. You can read about this work in Shubin’s award-winning book, Your Inner Fish, which was also made into a PBS show.
  • The discovery by Svante Pääbo and colleagues of the Denisovans, an extinct lineage of humans, based on sequencing a complete genome from the finger bone of a girl who lived tens of thousands of years ago.
  • The analysis by Tami Lieberman, Roy Kishony, and colleagues of the genetic adaptation of an opportunistic species of bacteria to the lungs of patients with cystic fibrosis. I’ve blogged about that paper here.
  • Here’s one from the long-term experiment in my own lab — the evolution of the ability to use citrate that arose in just one of the 12 populations and after more than 30,000 generations. There are nice summaries of this work in Carl Zimmer’s blog here and here.
  • A study by Hod Lipson and Jordan Pollack on the evolution of robots. I remember hearing about this paper and being shocked: “Wait a second. Robots are expensive, and most things go extinct during evolution. How could they even afford do this?” I had to read the paper to realize they were evolving virtual robots in a physical simulation of the real world. They then built and tested the winners in the physical world. And indeed, the robots worked as they had evolved to do.
  • Applying the mechanisms of evolution to artificial systems is a fascinating approach useful for both biology and engineering. One of my favorite basic-science uses of this approach was a paper where we used digital organisms – computer programs that self-replicate, mutate, and compete for resources – to show how very complex functions could evolve if simpler functions were favored along the way. These simpler functions provided building blocks for the more complex functions, illustrating how evolution works by tinkering and borrowing already existing structures and functions and using them in new ways. Incidentally, this work involved collaboration between a computer scientist (Charles Ofria), a philosopher (Rob Pennock), a physicist (Chris Adami), and a biologist (me).

Readers: Please feel free to add your own favorite examples of evolution in the comments section below.

[The picture below shows the Tiktaalik fossil discovered by Neil Shubin and colleagues.  It was posted on Wikipedia by Eduard Solà, and it is shown here under the indicated Creative Commons license.] Tiktaalik

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30 Comments

Filed under Education, Science

30 responses to “Favorite Examples of Evolution

  1. BW

    I’d have to include dogs evolving from wolves in this list, because dogs are fun. And the experiment using wild foxes to replicate their evolution http://www.americanscientist.org/issues/pub/early-canid-domestication-the-farm-fox-experiment.

  2. Herr Holz

    The tenrecs of Madagascar and their convergent evolution within one clade of many forms seen in mammals (e.g. hedgehog-like, otter-like forms etc)

  3. Russ Abbott

    One of my favorites is another example of convergent evolution. Humans and koalas both have fingerprints. They are so much alike that experts apparently can’t tell them apart.

  4. eratosignis

    Ok, ok, I accept citrate metabolism in E. coli is cool, and stuff like that, but sometimes tiny branches of the tree of life do something totally spectacular. What about MIMICRY in butterflies! Look at this picture!
    http://journals.plos.org/plosbiology/article/figure/image?size=large&id=info:doi/10.1371/journal.pbio.0040303.g001

  5. Speaking of beautiful organisms and wonderful experiments, here’s another of my favorite papers, this one on the evolution of plants in response to pollinators by my colleague Doug Schemske:
    http://www.pnas.org/content/96/21/11910.abstract
    Check out this figure from that paper for beautiful hybrids between two species of Mimulus:

  6. And on the subject of plants and pollinators, there’s the scientifically beautiful, historical, and accurate prediction made by Charles Darwin about the then-hypothetical long-tongued moth pollinator of an orchid from Madagascar, with its very long nectary:
    http://www.theguardian.com/science/lost-worlds/2013/oct/02/moth-tongues-orchids-darwin-evolution

  7. I’m a big fan of whales and cetacean evolution, with it’s really powerful fossil record. Kevin Padian did a great summary in the Kitzmiller trial: http://www.sciohost.org/ncse/kvd/Padian/Padian_transcript.html

    I also like the dinosaur to bird transition. Feathers, bird hips not from bird-hipped dinos, but from lizard hipped dinos, bird behavior in dinos, etc. Great stuff.

  8. Patrick Guder

    Some of my favorite examples of evolution are the South American endemic ungulates, like Macrauchenia and Toxodon. They were both weird and familiar. Extremely interesting.

  9. I’m not a fly guy, but I adore one example that I teach in Molecular Evolution under the topic of the “evolution of novelty.” The paper is by Jeong, Rebeiz, et al, explores the selective loss of pigmentation in a Drosophila species (D. santomea) on a West African island, where its pigmented ancestor, D. yakuba, also resides. They traced this loss of pigmentation to a mutation in a particular regulatory element, but what’s more, multiple independent mutations were found in the population. Thus, multiple adaptive mutations producing the pale phenotype are segregating in one population.
    http://www.sciencedirect.com/science/article/pii/S0092867408001141

    And although the genetic mechanisms remain to be discovered, it’s hard to beat the adaptive radiation of Hawaiian Drosophila.

  10. Dhananjay

    I am fascinated by evolution of birds of paradise and of bowerbirds. In one of David Attenborough’s documentary, he demonstrates the connection between elaborateness of bowers (built by male birds to ‘impress’ female birds) and availability of food in that particular region.

  11. Also on birds, there’s a superb film called the Ordinary Extraordinary Junco. It explains in clear and interesting ways the research performed by Ellen Ketterson and her team on the ecology, behavior, and evolution of these common backyard birds.
    Its multiple, short segments will make it great for showing and discussing different scientific issues in the classroom. Find it here:
    http://juncoproject.org
    I also briefly reviewed the film in my very first post on this blog: https://telliamedrevisited.wordpress.com/2013/08/19/welcome-to-telliamed-revisited/

  12. The often used example of Peppered Moth selection is an interesting talking point for discussing evolutionary processes, given its ambivalence. The reader can choose to infer either the positivity of the adaptability of life, or the negativity of our impact on nature.

    wikipedia.org/wiki/Peppered_moth_evolution

  13. Pingback: Botanical Wednesday: Monkeyflower madness

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  15. Rupinder Sayal

    Any discussion of examples of evolution is incomplete without my favorite Hox Genes, which are responsible for development of the basic body plan of animals. There have been many recent studies documenting how changes in Hox genes or their cis- regulatory elements (enhancers) have led to morphological changes in various animal lineages. Sean Carroll’s book “From DNA to Diversity” has more info for those interested.

  16. In class I really like using the repeated evolution of the pseudogenized enamelin gene in anteaters, pangolins, whales armadillos, sloths, & aardvarks: http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1000634 . Nicely illustrates loss as part of evolution and vestigial genes, plus a neat set of mammals.

    For human evolution Lactase-persistence allele is great, evolved at least 4 times. And now with ancient DNA we get to see its frequency change over time: Figure 2 here http://biorxiv.org/content/biorxiv/early/2015/03/13/016477.full.pdf

    Also the Tibetan high altitude allele at EPAS1 is a great human evolution story. Has it all, strong recent selection to a selection pressure we can understand and sex with archaic populations (Denisovians).

  17. The Italian wall lizards on Croatian islands (Herrel et al., 2008) that in ~30 generations evolved cecal valves and different head morphology in response to a different diet.

  18. One of my favorite examples of evolution is Nick Davies’ research into the interaction between cuckoos and those birds that they brood parasitize. For instance, there is an emerging co-evolutionary arms race between cuckoos that lay their eggs in robin nests (egg mimicry) and the robin host’s ability to discriminate between her own eggs and the impostor eggs.

  19. Here are 6 great case studies for teaching evolution, where my colleagues Peter White, Merle Heideman, and Jim Smith have pulled together what’s known about the ecology, genetics, physiology, etc. of each case — allowing evolution to be taught in, and integrated with, other courses.
    http://lbc.msu.edu/evo-ed/index.htm
    It also includes interactive games and simulations for many of the cases, like these on opsins and color vision in monkeys:
    http://lbc.msu.edu/evo-ed/Pages/Primates/Foraging/Foraging.html
    http://lbc.msu.edu/evo-ed/Pages/Primates/PatchGame/PatchGame.html

  20. frankschmidtmissouri

    Birds that lack capsaicin reception while mammals have it – a chemical defense against getting seeds chewed up by rodents while allowing gizzard-using organisms to distribute seeds.

    Hawthorn maggots developing into a new, reproductively isolated species after the introduction of apples in North America.

    The examination of Cairns’ result that looked Lamarckian on its face but led to an appreciation of error-prone DNA polymerases.

    • Your first two examples are very interesting ones. My retired colleague Guy Bush did a lot of interesting work on the Rhagoletis pomonella story: http://en.wikipedia.org/wiki/Apple_maggot
      http://www.msu.edu/~bushfly/pubs.html

      Your third example, on the Cairns’ story of quasi-Lamarckian mutations, is complicated and involves more than just error-prone DNA polymerases. With my former student John Mittler, we looked at a couple of the early cases of so-called “directed mutation” and found there were problems with missing controls and other aspects of experimental design and interpretation. For those interested in these issues, here are several reviews (“oldies but goodies”):
      Lenski, R. E., and J. E. Mittler. 1993. The directed mutation controversy and neo-Darwinism. Science 259:188-194.
      Moxon, E. R., P. B. Rainey, M. A. Nowak, and R. E. Lenski. 1994. Adaptive evolution of highly mutable loci in pathogenic bacteria. Current Biology 4:24-33.
      Sniegowski, P. D., and R. E. Lenski. 1995. Mutation and adaptation: the directed mutation controversy in evolutionary perspective. Annual Review of Ecology and Systematics 26:553-578.