Go back far enough in our history–maybe about 650 million years–and you come to a time when our ancestors were still invertebrates. That is, they had no skulls, teeth, or other bones. They didn’t even have a brain.
How invertebrates became vertebrates is a fascinating question, made all the more fascinating because the answer tells us something about how we got to be the way we are. In order to reconstruct what happened, scientists can study several different kinds of evidence.
The New York Times, February 21, 2006
Sooner or later, everyone encounters a kentia palm. Its ability to grow in low sunlight has made it one of the world’s most traded houseplants.
“If you’ve been to a wine bar or to Starbucks, there may have been one in there,” said William Baker, a botanist at the Royal Botanic Gardens in Kew, England.
“Whether you realize it or not, you’re familiar with this palm,” he said.
Continue reading “Palm Trees and Lake Fish Dispel Doubts About a Theory of Evolution”
This is why I was so lucky to get Carl Buell to illustrate my first book.
Originally published February 21, 2006. Copyright 2006 Carl Zimmer.
In tomorrow’s New York Times, I have an article about how new species evolve. It describes new research into how a population can split into two species. The idea that species can evolve when populations get geographically isolated is well-supported by evidence, but the idea that individuals living side by side can split apart (called sympatric speciation) has sparked more controversy. The late biologist Ernst Mayr was the lead champion of the geographic isolation mechanism, and he was always skeptical of claims of sympatric speciation.
You and an oak tree have something in common: you’re both big. Unlike viruses and bacteria, you and an oak tree are both made up of trillions of cells. There’s something else you and an oak tree have in common: you both began as an individual cell, which then divided again and again, its daughter cells differentiating along the way to produce tissues. In your case, they turned into bone, muscle, liver, and such. In the oak’s case, the cells became bark, leaf, root.