Hello again everyone! I'm excited about this weeks reading, we are starting to see some good examples of the evolutionary process as well as some of the primary examples that helped Darwin shape his realizations. I found a few of the examples very interesting and I really enjoyed reading about the predictions that were made by two different people (Darwin & Wallace) around the same time periods, with limited knowledge of each others research. This, to me, was great to read about. Finding that multiple researchers were finding some of the same information at the same time shows me that there is a decent amount of merit to what they proposed.
When i was getting through the examples in the text there were a few things that stuck out to me and a few things I had some questions about.
1- The idea that the pollinators (Hummingbirds, Bees, etc.) had the same tendencies towards what we described as 'beautiful' flowers. Hence, causing the flowers that were more colorful and pleasing to look at to become pollinated more often and have better chances of surviving. Also falling under this same idea was the idea that the hens are more attracted to a mate that had a more flamboyant and colorful than others that looked a little more plain, again using the same presumption that they are seeing these colors the same way we see them.
2- Natural Selection. There are so many good examples of this in the book, and the way it ends up working always seems to be a cycle to me. The one i saw the cycle in the most was the Canary. The idea that the females were attracted to the males song and it caused a sort of arousal that caused the likelihood of them mating to increase. This, in turn, would help to develop more males to be born that had the more attractive song and would eventually cause more mating. This is the big concept behind Natural Selection, Right? I'm new to the details of Natural Selection and the majority of the ideas in this chapter include the female making a choice of its mate, so I wanted to clarify the process and what parameters constitute that it is indeed Natural Selection.
Okay, i don't want to take up all the main points, I hope to hear from everyone soon. Thanks again for joining me!
Finally had time to finish the chapter and I guess I really don't have a lot to add to what you guys have said. Most of the chapter seemed pretty straightforward, not really much that seemed difficult to understand. Like Heather said, Dawkins sets the stage for getting down to business about natural selection by "softening us up" (lol) with his discussions of artificial selection and sexual selection. And I thought it was a nice transition when we moved from humans being the artificial selectors to birds and bees and insects (totally agree that it's truly amazing the way all these co-evolve.)
I guess there's 2 main points that really jumped out at me. The 1st is the discussion about the process of natural selection, while being similar in many points to these other processes, is unlike them in one very important way: there is no "choosing" agent in natural selection at all. I thought it was interesting that it was Darwin himself who, innocently, basically caused the problem by talking about evolution in a manner that seemed to attribute some kind of guiding design behind it. Like saying that "natural selection is daily and hourly scrutinizing..." obviously gives the wrong impression. I felt this was important because it still seems to be one of the big problems that people have when trying to really understand evolution. I watch a lot of programs that deal in one way or another with evolution and they are always saying things in such a way that it sounds like evolution is some force that is proactively acting on a species with end-result adaptations in mind. That is exactly not true.
The other point i was struck by is when Dawkins points out that "Artificial selection is not just an analogy for natural selection. Artificial selection constitutes a true experimental - as opposed to observational - test of the hypothesis that selection causes evolution." That was one of those "ah-ha!" moments for me :)
One example of the adaptations that plants have made that i thought was pretty incredible was the "bucket orchids", the ones where the bee falls down in the pot and the has to crawl out through a little side hole, where it's trapped while "pollinia" are glued to it's back, held in place till the glue dries and then is released to hopefully carry the pollinia to another orchid. Wow! that is quite a series of steps. Very cool.
First, it's really hard for me to know what a chapter is, since this is a talking book. So if I get ahead, sorry.
As you can tell from my avatar, I'm a dog lover. Dawkins goes into the idea that we probably (actually, he sounds pretty sure) didn't domesticate the dog. The dog is a result of natural selection. The artifical selection (fine tuning of different breeds) came later after we learned the concept of artificial selection.
I'm wild about this idea and had studied it in detail before Dawkin's brief description. But since we are reviewing this book I will stop here.
Dawkins does a wonderful job explaining how science measures time and age. It was a nice review for me. Since this book has creationists in mind, he built this all up to explain how the flood theory could never be. I'm guessing his younger self never thought he would have to explain how "Head for the Hills" couldn't have happened.
PS - his build up of artificial and natural selection and dating is to understand a concept in chapter 4.
I thought that whole section was very fascinating, well really everything in this book is, but anyway. A very interesting point about how when domesticated animals go feral that they very quickly sort of revert to something close to their pre-domesticated state. Yet, though we know that dogs are descendants of wolves, the state they revert to in the wild is more like "village dogs" than wolves; which implies that the wolf went through an intermediary stage where it was "self-domesticating" by becoming adapted to live closer to humans and feed off their refuse piles. Absolutely fascinating!
And also, though I don't think Dawkins said this, and it might be wrong, but it makes some sense to me [ah well, i guess it's all implied in the whole "village dog" thing]: tied in with what you mention next, Pleiotropy (hah, i'd never have remembered that term if you hadn't brought it up!) that in this long process of the wolves becoming adapted to this environment, selecting for that perfect zone of "flight distance," were selecting the trait that would lead to them being able to be domesticated; as well as indirectly (pleiotropically) selecting the genes that would change their appearance from wolfiness to dogness!
Maybe this could be the next book: "Dog Who Couldn't Stop Loving: How Dogs Have Captured Our Hearts for Thousands of Years" by Jeffrey Moussaieff Masson
How do you start? First get a bunch of folks to agree to get the book?
Okay. Great. I am part of a Atheist Dog Lovers group on TA. I'll ask them over and then ask this group who is interested.
Sorry to go off subject.
maybe we should just post whatever further comments we want to make in the original thread "The Greatest Show on Earth" - Read Along!
I'm still reading the book and would like to post comments, it helps to retain the information.