Life Sciences
stcynic | March 22, 2004When we talk about evolution, we almost always talk about animals or microbes, with only a rare mention of plants. The reality, though, is that evolution is a powerful theory in explaining the natural history of flora as well as fauna. The study of plants is called botany. Last summer, the Botanical Society of America released a statement about the importance and validity of evolution that is a must-read for anyone who wishes to understand this issue. One of the great things about this statement is that it emphasizes the usefulness of evolutionary theory, the fact that plant biologists use…
stcynic | March 12, 2004Rob McEwen has left a comment on a post that has slipped way down the page, and as it's worth responding to and fisking in some detail, I thought I'd bring it up top to answer it.
Pre-script: Turns out this guy left this same comment, word for word and breathless exclamation point for breathless exclamation point, on Paul Myers' blog. Hilarious.
In his comment, Rob pretty much pulls out the first 3 chapters of what I facetiously refer to as the Creationist Jokebook. This consists of a laundry list of arguments that anyone who has followed this dispute for any period of time has heard over…
loom | February 29, 2004As biologists figure out more about how life is, they can then figure out how it got to be that way. First there were genes. Mendel noticed that somehow the wrinkles on wrinkled peas could be transmitted down through the generations, even if some of those generations had no wrinkles at all. It turned out that the wrinkles were the result of a gene; a different version of the gene produced smooth peas. For much of the twentieth century, evolutionary biologists worked out how changes in genes produced evolutionary change. A mutation that alters one position in a gene (or chops out a whole chunk…
stcynic | February 27, 2004Tim Sandefur has a "guest blogger" making entries on his blog by the name of Matt Dunn. Dunn is a dentist and no doubt a very bright guy, but he has been making comments about evolution that I can't help but respond to. It began with this post about a dentist's convention he attended and the keynote speaker referring to the design of the jaw as evidence for Intelligent Design (ID):
I asked Dawson if he could expand on his creator reference. He obliged by offering a philosophical comment: The more you understand about the human masticatory apparatus, the harder it becomes to remain an atheist…
loom | February 6, 2004Abominable is not the sort of word that most people may associate with flowers, but for Darwin, it was a perfect fit. He saw life on Earth today as the result of millions of years of victories and defeats in the evolutionary arena. Flowering plants, by that reasoning, were among the greatest champions of all. There are some 250,000 known species of flowering plants, and the total is probably double that. The closest living relatives of flowering plants (pine trees, firs, gingkos, and the likecollectively known as gymnosperms) make up a grand total of just over 800. These numbers are all the…
stcynic | February 3, 2004Rusty posted a brief response to my last entry on the testable creation model. I'll paste the comments here because it allows a bit more space to respond:
Ed, you really are tempting me to respond...
I really think a good, long conversation on this topic would clear a lot of things up. We would each still be sitting in our respective camps, but we'd probably have a better understanding of what the other was positing.
Let me explain in the next comment...
Case in point is the "order of appearance" argument you make (e.g., Wolf-like creature to whale). Both models support the fossil data. But…
stcynic | January 30, 2004To continue the dialogue with Rusty Lopez from the New Covenant blog, let's examine his latest posting. I'm going to do this one a bit differently so as not to lose the threads of each specific point of dispute. I'm going to divide this post by those areas and label them as such, and I will put my original argument in plain type, then Rusty's response in italics, then my new response in plain type again. That way each issue can be followed as the argument has developed.
1. The definition of testability
I had written:
"It appears that both he and Ross use what I regard as a rather…
stcynic | January 28, 2004In this entry, I will deal only with the brief note that Rusty Lopez made in reference to a testable creation model. In the next few days, I'll post a longer and more detailed critique of the model presented by Hugh Ross that Rusty referenced in his note. I'll put his statements in italic and my own responses in plain type.
A Scientifically Testable Creation Model...How is this possible? Are we saying that science can prove creation?
No. Reasons to Believe is saying that we can test the predictions made by competing scientific models.
We can at least begin with an area of agreement. Testing a…
loom | January 14, 2004The emotions that other species summon up in the human brain are perplexing. A lion inspires awe and respect. It is the king of the jungle, a great name for a football team, a noble guardian of the entrance to the New York Public Library. A tapeworm, on the other hand, summons disgust mixed with a little contempt. You will never find yourself cheering for the Kansas City Tapeworms. But are these species really so different? Both animals get their nutrition from the bodies of other animals, and tapeworms are arguably more sophisticated in the way they get their food than a lion. Tapeworms…
loom | January 12, 2004Last week I briefly mentioned some stark estimates about the potential extinctions that could be triggered by global warming. Since then, some global warming skeptics have tried to pour cold water on these results by making some dubious claims about natural selection and extinctions. While I have reported about global warming from time to time, I leave blogging on the subject to others (particularly David Appell over at Quark Soup). But in this case, evolution is drawn into the mix.
Here, in a nutshell, is what the scientists wrote last week in their Nature paper (which the editors have made…
loom | December 22, 2003Evolution isn't simply about the genes you gain. It's also about the genes you lose.
The word loss has a painful, grieving sound to human ears, and so it can be hard to see how it can have anything to do with the rise of diversity and complexity in life. And until recently, evolutionary biologists didn't pay much attention to lost genes because they were preoccupied with the emergence of new ones. New genes, they found, can be produced in many ways. A gene can get accidentally duplicated, for example, and the copy can mutate, taking on a new function. Or pieces of two separate genes can get…
loom | December 15, 2003Darwin's spirit lives on in everything from the Human Genome Project to medicine to conservation biology--the three topics I covered in my post on Friday. It also lives on in brain scans.
While Darwin is best known for The Origin of Species, he also wrote a lot of books in later years, most of which explored some aspect of nature that he showed revealed the workings of evolution. His examples ranged from orchids to peacock tails. In his 1872 book, The Expression of the Emotions in Man and Animals, he proposed that the expressions we humans use--our smiles, our frowns, and so on--are part of a…
loom | November 12, 2003Time always marches forward, of course, but does evolution?
It's certainly easy to impose a march of progress on the course of evolution. That's why the sequence of apes transforming into humans as they march from left to right is so universal. Of course, there are also pictures in which Homo sapiens, having risen up to noble, upright proportions, begins to crouch back down again, until he (never a she, I've noticed) is crouching in front of a computer or a television or facing some other ignoble end. As I wrote in Parasite Rex, this anxiety--an anxiety mostly about ourselves and not about…
loom | November 7, 2003The other day I (among others) came down on Gregg Easterbrook for his poor grasp of science. Finding myself procrastinating today, I wandered over to his blog and had yet another good laugh. In a post today, he actually displays some interest in evolutionary biology. After discussing some work suggesting that wine might be able to prolong life, he gets into the evolution of longevity. I raised my eyebrows at this point, thinking perhaps he'd moved away from the muddled stuff he's written about evolution in the past. But then the goofiness returns.
First he describes how experiments to extend…
loom | October 29, 2003Evolution is nature's great R&D division. Through mutation, natural selection, and other processes, life can find new solutions for the challenge of staying alive. It's possible to see a simplified version of this problem solving at work in the lab. The genetic molecule RNA, for example, can evolve into shapes that allow it to do things no one ever expected RNA to do, like join together amino acids. Over millions of years, evolution can solve far bigger problems. How can a mammal became an efficient swimmer? How can a bug fly?
Humans would like to build ocean-going vehicles as efficient…
loom | October 26, 2003When Charles Darwin was thrashing out his theory of evolution, he would doodle sometimes in his notebooks. To explain how new species came into existence, he wrote down letters on a page and then connected them with branches. In the process, he created a simple tree. Across the top of the page, he wrote, "I think."
That single tree has given rise to the thousands of trees that are published in scientific journals these days. A particular tree may show that humans are more closely related to chimpanzees than gorillas. It might show how the SARS virus in humans descends from viruses in other…
loom | October 21, 2003The Great Lakes of East Africa swarm with fish--particulary with one kind of fish known as cichlids. In Lake Victoria alone you can find over 500 species. These species come in different colors and make their living in many different ways--sucking out eyeballs of other cichlids, scraping algae off of rocks, and so on. What's strange about all this is that the Great Lakes of East Africa are some of the youngest lakes on Earth. By some estimates, Lake Victoria was a dry lake bed 15,000 years ago. All that diversity has evolved in a very short period of time.
East African cichlids are therefore…
loom | October 7, 2003Thanks again for the comments on my previous two posts about eugenics. As a novice blogger, I was surprised by their focus. I expected comments about the past--the historical significance of the eugenics movement--but instead the future dominated, with assorted speculations about the possible futures that genetic engineering could bring to our species. By coincidence, I've been thinking about the future as well, but from a different angle, thanks to a pair of papers in press at Trends In Ecology and Evolution. Instead of introduced genes, they're interested in introduced species.
Before…