Science a GoGo's Home Page Forums General Discussion Not-Quite-Science Forum Darwin's Finches Evolve Before Scientists' Eyes

"For the first time scientists have observed in real-time evolutionary changes in one species driven by competition for resources from another.

In a mere two decades, one of Charles Darwin's finch species, Geospiza fortis, reduced its beak size to better equip itself to consume small sized seeds, scientists report in the July 14 issue of the journal Science. "

http://www.livescience.com/animalworld/060713_darwin_finch.html

Maybe my understanding of evolution is flawed. Someone help me to explain what I believe.
I've always understood evolution as speciation and natural selection as the proposed mechanism for evoltution. I have a hard time understanding when evoltution occurs. In other words, at what point do we say that a creature has evolved? In a simplistic way I understand a species to be creatures that will reproduce under natural circumstances. So why do they term the finches as evolutionary change? This is not speciation but adaptation by natural selection. This is nothing new, we see this all the time. So why is this article remakarable?

Evolution can be seen within two generations. One in which a change occurs in the DNA and the next to see if the change has been passed, successfully, to the next generation.

We know now too that changes may not be expressed just in DNA but also in the expression of previously existing genes based on the sugar coating DNA carries with it.

No doubt serious biologists can and will disagree but I'd argue evolution is always happening at some level. Whether the changes are selected for and survive long term is quite another matter.

DA,
That seems to me like the ultimate in microevolution. If you are suggesting that evolution occurs with changes in DNA, what are the standards, in other words, change relative to what? There are no two sets of DNA between two members of the same species that are the same, so does that mean that every species that has offspring is an evolutionary progression from its parents. Forgive me if I sound ignorant but I've never heard this point before.

ive heard it said (teachers mainly) that evolution is a constant thing. I was told in school many years ago that every generation has some variations. some are valid and can be passed on, while others die out either due to it being damaging to the life expectancy of the lifeform that carries it, or to its ability to pass it on.

i was also told that one of the limiting factors to its being passed on was the fact that it only had a 50/50 chance with of going into each offspring. if there were few offsprings in did not have much of a chance of surviving the second generation.

i was also told that it had to do something to increase the lifeforms ability to survive or it was not usefull to the lifeform and would likely be lost. very few changes passed this test.

in this case, the bird's beak gave it a food source that its cousins did not have, thus could not compete for. since it had more food, it had more offspring. thus it passed the test and was passed on. this made it a viable evolutional change.

my teacher told us that the bigger the dna chain, the more likely there was to be a mutation.

I think the problem may be that you are not thinking in truly evolutionary terms, db. Our entire notion of speciation - the Linnaean System - was created by a creationist. What is the implication of that fact? The implication is that he believed that species are static.

You think that evolution occurs when an individual of species A produces an individual of species B. That's not how it works. Evolution occurs when the population at time T2 contains different genetics than at time T1. Evolution includes - it MUST include - more than just speciation events.

Imagine a near-continuum for a moment. A produces B produces C, etc. B is the same species as A, EVEN IF EVOLUTION HAS OCCURRED, if As and Bs can interbreed and produce viable offstring. That will be true most of the time. C is also the same species as A. Now let's go further...C -> D, D-> E, E ..... Q. Suddenly Qs can breed successfully with everything from D through P and Q, but it can't breed with As and Bs any more.

This means that, for example, F is the same species as A and P, BUT A and P are not the same species. How did this happen? It turns out that the property "is the same species" is not transitive (to put it in mathematical terms).

How did this come about? Because Linnaeus assumed species were constant.

Thanx Fallible, I follow you perfectly. I'm gonna need some time to ponder this.

good explination, tff

The fact that the finch, "reduced its beak size to better equip itself to consume small-sized seeds," as the article says, shows that that the bird's beak size didn't randomly change. The birds did it, a random mutation with no Creator behind it didn't change it just at that time when that beak size was needed. Evolution is a fake. For more information, go to www.freewebs.com/biblicalcreation and go to the link on creation vs. evolution

Tim, you don't know the first thing about the subjects of science, evolution or finches. You are intellectually lazy. Do some real homework and then come back to make a contribution on the subject.

Tim, you don't know the first thing about the subjects of science, evolution or finches. You are intellectually lazy. Do some real homework and then come back to make a contribution on the subject.

But worse yet you don't know the first thing about biblical creation either and that is really lame. If you are going to claim biblical creation at least understand what it is you believe.

Genesis 1:11 God creates plants
later ...
Genesis 1:16 God creates the sun
Oops!

Don't you just hate it when the tooth fairy runs her nose right into the brick wall of reality? Even a 5 year old child knows you need to create the sun before the plants. How inconvenient.

Go to www.freewebs.com/biblicalcreation if you want to see a great example of a presentation of comic-book science, or if you just want a good chuckle. That's what non-scientists and 10th tier pseudoscientists say on the subject. These are the guys who have contributed next to nothing to science.

If you're interested in what ACTUAL scientists say on the subject of evolution, try http://www.talkorigins.org/

Here's what nobel laureates think:
http://www.talkorigins.org/faqs/edwards-v-aguillard/amicus1.html

Tim has proven he has no knowledge of or interest in science. The comic book version fed to him by his cult makes him feel good because he is going to someday get yanked up to heaven by his pony tail whereas I am going straight to hell with my friends.

Party!

Why would you want to go to hell?

Why do you think I'm involved in a cult. I'm not an evolutionist. If I was, then I'd be in a cult.

Your cult

1) Prevents you from accepting what real scientists say
http://www.talkorigins.org/faqs/edwards-v-aguillard/amicus1.html

2) Prevents you from even attempting to make a scientific argument - noticably lacking in your posts, so far.

3) Instructs you to make unsupported assertions as per your previous posts.

4) In fact, prevents you from even trying to understand the subject.

You should be posting in a religious forum - not a science forum.

Tim asks:
"Why would you want to go to hell?"

Because it doesn't exist. There is no heaven. There is no hell. And there is not one shred of evidence anywhere that either exist. If you think otherwise by all means don't point to your cult's website but point to some independent evidence.

PS: Authorless books are not evidence.

Tim asks:
"Why do you think I'm involved in a cult."

Becuase you write stuff like this:

"I'm not an evolutionist. If I was, then I'd be in a cult."

You believe in something that not only isn't true but for which there is no evidence that supports the proposition that it is. That is a clear sign of brainwashing. Find a deprogrammer ... you can be helped.

And Kate should demonstrate some actual desire to promote science knowledge and stop allowing these people to post.

They are obviously cult members or in need of psychological support services.

My take on Tim is that he is 13-17 years old, a "true believer" in what his family or cult is teaching and, due to brain washing, essentially incapable of doing anything independent of them. So far he's demonstrated, for example, an inability to even use google to look things up.

Tim:
Welcome to the Forum. Does your Guru know that you're in an Internet Cafe? Take my advice- gather up your orange saffron robe, your prayer bells and boogie on back to the ashram, or the colony, or wherever it is they've got you.

DA morgan contributed:

"No doubt serious biologists can and will disagree but I'd argue evolution is always happening at some level. Whether the changes are selected for and survive long term is quite another matter."

Sums it up nicely. TheFallibleFiend's contribution from 22 July, also briliant.

DrBarr wrote:

"This is not speciation but adaptation by natural selection. This is nothing new, we see this all the time. So why is this article remakarable?"

Years ago I read a book by Jonathan Weiner (1995) called "The Beak of the Finch". The original research also tells us a great deal about how species can come together and separate depending on the environment they have to survive in. The concept of "ecological speciation" is in fact the only debate of consequence amoung evolutionary biologists. Does anyone know any sites?