Speciation

Okay, I'm pretty new to Biology. I remember being totally disinterested in high school but I'm going back to school to study anthropology (possibly biological anthropology if I'm smart enough )

So, since I'm already 38 and would like to get my B.S. quickly so I can move on to my Masters I'm going to take the CLEP for Biology and as many other courses I can.

That being said, I've got a Self Teaching Guide for Biology and I also go an Evolution textbook from Barnes and Noble. I have to read everything 2 or 3 times to really grasp it but it's really remarkable and fascinating. I wish I had got into this stuff back in high school. I was too busy chasing boys and smoking weed though

What I don't really understand is how a common ancestor could give rise to so many varied animals. I understand that we're all distantly related and DNA tells us this. I just don't see how you go from fruit fly to human ( I know it didn't happen exactly like that but you get my point). I can see species changing but how do you start with ONE type of bacteria to get an animal and then all the different classes and phylum, et cetera?

Please help!

[Smellyoldgit]

The ahem... "serious" bits of this thread may be of interest.

We're still waiting for 10's next instalment.

[Tenspace]

Ouch! Stop poking

Yes, it's time for a new installment. I'll write it this weekend.

Ellie, go pick up Dawkin's "The Ancestor's Tale". It does a great job of explaining how all this diversity came about. It's the size of a college textbook, but much more interesting.

If you have any specific questions, feel free to post them in this thread, and I'll answer them for you.

[Sternwallow]

Ellie Arroway wrote

Okay, I'm pretty new to Biology. I remember being totally disinterested in high school but I'm going back to school to study anthropology (possibly biological anthropology if I'm smart enough )

So, since I'm already 38 and would like to get my B.S. quickly so I can move on to my Masters I'm going to take the CLEP for Biology and as many other courses I can.

That being said, I've got a Self Teaching Guide for Biology and I also go an Evolution textbook from Barnes and Noble. I have to read everything 2 or 3 times to really grasp it but it's really remarkable and fascinating. I wish I had got into this stuff back in high school. I was too busy chasing boys and smoking weed though

What I don't really understand is how a common ancestor could give rise to so many varied animals. I understand that we're all distantly related and DNA tells us this. I just don't see how you go from fruit fly to human ( I know it didn't happen exactly like that but you get my point). I can see species changing but how do you start with ONE type of bacteria to get an animal and then all the different classes and phylum, et cetera?

Please help!

It is amazingly elegant. For example all dogs are directed (artificial selection) evolution applied to Wolves over a span of a few thousand years. See the incredible variety obtained in such a short time. There are still Wolves because species do not "turn into" other species, they split like the branches of a tree.

In general a new species begins when part of an existing population of critters is somehow prevented from mixing with the rest (isolated, e.g. by Geographic barriers like rivers or mountain ranges). Then the natural variation of individuals within the two populations have no way to average back into the whole group. When the accumulated differences are great enough, that is, when the two populations have diverged too much for them to interbreed any more, you now have two species where once there was just one. Of course, in the natural world, this takes upwards of millions of years just because the selection process is slow and wandering.

As long as there is enough time (like a couple Billion years), the process of evolution by natural (and likely sexual) selection, can achieve incredible complexity, all from trying to survive in the changing environment, and it is all done without the ham-fisted intervention of a celestial blow-hard.

Remember that, once we (creatures) invented sex, we were no longer slaves to mutation for our only variation. We could evolve that much faster which can mean the difference between species survival or extinction when changes in the environment happen quickly.

Tenspace wrote

Ouch! Stop poking

Yes, it's time for a new installment. I'll write it this weekend.

Ellie, go pick up Dawkin's "The Ancestor's Tale". It does a great job of explaining how all this diversity came about. It's the size of a college textbook, but much more interesting.

If you have any specific questions, feel free to post them in this thread, and I'll answer them for you.

I picked it up about a week ago and have been reading it. I don't really find it nearly as interesting as Carl Sagan's Shadows of Forgotten Ancestors I don't know, Dawkins is bland compared to Sagan in my opinion. I like how Sagan exlpains why we say "Fuck You" and most of the time don't even know what it means (referring to chimps).

Thank you for all your responses.

I'm really having trouble with evolution. I mean, I'm agnostic but it just seems way to convenient that, for example, just happened to evolve lungs to breath the oxygen in the air. From what I read in Sagan's book Shadows of Forgotten Ancestors, a very long time ago there was no oxygen. So when oxygen became abundant and hominids were roaming the earth at what point did the organism that was our common ancestor decide it needed lungs. And where did it get the information to build lungs. And where are all these eukaryotic cells getting all their information on how to "run." Everything seems like a machine and it seems "designed." I"m sorry but I seriously cannot get away from thinking this. If there was a god I don't think it would have emotions or be anything like what religious folk thing "God" is. I would guess it would just be "the intelligent force of nature that encompases everything." It just seems like the whole planet is one big symbiotic well oiled machine and what I want to know is where the hell does all this intelligence in nature come from? Cells don't have brains so how did we all evolve from a single celled organism with no brain?

I'm not trying to prove god exists, I'm just saying, I"m not buying into evolution from a common ancestor. And I'm reading this book http://www.oupcanada.com/catalog/9780199255634.html


so I'm not just lightly skimming literature.

[Eva]

nature does not have intelligence........

Eva wrote

nature does not have intelligence........

I meant intelligence (in animals) in nature.

Anthropologist Jeremy Narby's book called Intelligence in Nature is a great book on this subject.

http://www.amazon.com/Intelligence-N.../dp/1585423998

Intelligence in Nature offers overwhelming illustrative evidence that independent intelligence is not unique to humanity. Indeed, bacteria, plants, animals, and other forms of nonhuman life display an uncanny proclivity for self-deterministic decisions, patterns, and actions. The Japanese possess a word for this universal knowing: chi-sei. For the first time, Narby presents an in-depth anthropological study of this concept in the West. He not only uncovers a mysterious thread of intelligent behavior within the natural world but also probes the question of what humanity can learn from nature's economy and knowingness in its own search for a saner and more sustainable way of life.

[Eva]

i think this author is full of woo. to use the term in this manner is misleading. note how the review also uses the term "knowingness".
check other books that don't anthropomorphize nature.

[Irreligious]

Ellie Arroway wrote

I picked it up about a week ago and have been reading it. I don't really find it nearly as interesting as Carl Sagan's Shadows of Forgotten Ancestors I don't know, Dawkins is bland compared to Sagan in my opinion. I like how Sagan exlpains why we say "Fuck You" and most of the time don't even know what it means (referring to chimps).

OK. I will pick up Sagan's book but, I wanna know in a nutshell, why do we say "fuck you," or its equivalent across the spectrum of the species, according to Sagan?

It's learned behavior, I assume, but why are we compelled to perpetuate it? And, of course, we know it's supposed to be a grave insult, but why should that be, logically?

[Irreligious]

Eva wrote

i think this author is full of woo. to use the term in this manner is misleading. note how the review also uses the term "knowingness".
check other books that don't anthropomorphize nature.

Good point, Eva. It is our tendency to anthropomorphize which, I would guess, is why the species invented gods. Superficially, it seems logical that we would have arisen from something that is like us, with thoughts and needs much like our own.

It's pretty hard to think outside of ourselves and our human experiences, because there's no real reference point for doing that.

[Kate]

My kitty needs to cuddle with me on the couch while we watch Kill Bill.

She loves that story.

[ghoulslime]

Kate wrote

My kitty needs to cuddle with me on the couch while we watch Kill Bill.

She loves that story.

I wish I could fondle your warm little pussy in a very delicate manner.

[Kate]

[Eva]

kate, does your pussy scratch?