My Dodo Story


Let’s give a hearty welcome to guest blogger Rick. Rick will be making occasional posts to the Chawed Rosin in future. Mix it up a bit.

This is a story I heard in college, and have since repeated it many times.

Living on the island of Mauritius in the Indian Ocean, Raphus cucullatus, or the dodo, couldn’t fly, nested on the ground, and was unafraid of people due to lack of predation. Sailors, despite the dodo’s reputation for tough, stringy eating, herded them onto awaiting boats. Introduced species such as dogs, pigs, and monkeys plundered their nests. Loggers destroyed the forests. By 1681, they were extinct.

The dodo is perhaps the most famous of extinct species. It looks funny, has a funny name, and has entered the language with phrases like “dead as a dodo,” and “gone the way of the dodo.” Sort of amusing, if driving a species to extinction can be thought of as amusing. Enter the Calvaria tree!

In 1977, Stanley Temple published Plant-animal mutualism: coevolution with Dodo leads to near extinction of plant in the prestigious journal Science. It turns out the Calvaria tree has a seed coat that’s as hard as a peach pit, and won’t germinate. In 1977 there were only 13 trees left, all of them 300 or more years old. Temple speculated that the dodos would swallow the fruit, and their gizzards would abrade the seeds enough for them to sprout. As an experiment, Temple force-fed 17 seeds to turkeys, his dodo-substitutes. Seven of the seeds were crushed. Of the 10 that survived, three germinated. So laugh if you will, but the demise of the dodo lead to the near-demise of the tree that had come to depend upon it.

So that’s my dodo story. Interesting, isn’t it? Well, it seems it isn’t true. In fact, Temple’s paper has become a lesson on how not to write a paper. The Calvaria tree has no growth rings, making it difficult to determine its age, but the evidence suggests a variety of ages on Mauritius, young and old. Also, Temple’s estimate of 13 trees was inaccurate. The young trees do not have the distinctive, mangrove-like appearance of mature trees, and there were actually hundreds on the island. Temple failed to measure the abrasions the turkey gizzards inflicted on the seeds. Did the seven that failed to sprout have fewer abrasions than the three that did? Who knows? Finally, Temple made a fundamental error by not having a control. He failed to try germinating uneaten seeds. The seeds germinate without the benefit of mechanical abrasion. They sprout on their own. The basis of Temple’s hypothesis, that the Calvaria tree was dependent on the dodo for repoduction, was easily proven false.

I can’t tell you how disappointed I was to learn this. I loved this story. Short, easy to tell, easy to picture. The dodo as hero. It was perfect. All I did was google “dodo tree seed”. I just wanted to know the name of the tree, maybe refresh the memory a bit. Now I kind of wish I hadn’t.

Why did Science publish his paper? Hard to say, but perhaps the editors found the story very interesting, and were hypnotized by its appeal. It was the redemption of the dodo, and they liked it.

Calvaria tree

~ by Rick on July 2, 2009.

11 Responses to “My Dodo Story”

  1. Welcome, Rick! Thanks for the fun story. Always nice to get a reminder that peer-reviewed articles aren’t the end of the story. The real value in a published paper is when someone is able to reproduce the results while doing another experiment, or is able to build on the information somehow.

    Scientists are humans, too, so we rely on each other to catch unintentional mistakes. Sounds like these folks made quite a few!

  2. Actor, broadcaster and opera singer Jan Rubes has passed away.
    This is really a terrible loss- he was a wonderful singer, actor and gentleman.
    We’ll miss him. May he rest in peace.

  3. Trees don’t need no stinking Dodo’s.

  4. Poor Dodo’s, even in extinction their glory is taken away.

  5. hi can you write the story how the dodo became extinct?

  6. I can’t write the whole extinction story. The dodo was unafraid of predators because there were no predators on their islands, and when people + dogs + cats + pigs + monkeys arrived, they didn’t stand a chance. It wasn’t the people so much, but the animals that plundered their nests and disrupted their lifecycle that did them in. For a more complete answer, click on the dodo picture at the top of the page.

  7. Be more forgiving to Temple’s paper: he stated himself “….led me to hypothesize the following mutualistic relationship between
    Calvaria and the dodo. ….”. It’s a hypothesis, nothing more.

  8. Hi Eveline. A paper like this begins with a hypothesis that is then tested. The paper is the results of the test, not the hypothesis itself. I loved this hypothesis, as did the professor that told it to me. But hypothesis is a strong word in science, and Temple’s paper deserves no slack. No paper

  9. dodo

  10. i’m sad

  11. The Last Dodo

    The Dodo (raphus cucullatus) became extinct by the end of the 1600’s. Although the exact date The last dodo died is unknown,the last intact specimen was consigned to flames in ignorance, at The Ashmolean Museum, Oxford 1755.

    was it shabby and rotten, was it creepy and rude ?
    was the curator just in, a house cleaning mood ?

    was it bad taxidermy, was it dusty and old ?
    was it flea bitten, mangy or covered with mold ?

    was it really subversive, was it smelly and putrid ?
    was it aesthetically weak, were the trustees all stupid ?

    all questions have answers, but we’ll likely get spurned…
    if at Oxford, we ask, Why the Dodo got burned ?

    Rhyme published in
    ‘ BRUSSELS SPROUTS & UNiCORNS ’ also not peer reviewed

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: