Darwinism help.?

Question

I am trying to win an argument, and I need some help coming up with a specific example for each of the following points of Darwinism
1) The nonconstancy of species
2) Branching evolution, implying common descent of species
3) gradual changes in species
4)Natural selection

Answer 1

1. Species are variants. Every time a horse and a donkey get together to produce a mule, essentiallisim is dealt a blow. Look at the ring species of salamanders that ring the Californian Central Valley. One end of this ring species can not mate with the other end.

2. I like the overwhelming genetic evidence here. The conservation of the same type HOX genes across many species. Taxonomic information is good too, unless your one of those claddists!

3.Artificial selection needs to shut up those creationists, but it does not. Look at a Dachshund; 12,000 years ago that was a wolf. Actually, it still is, but you can not argue against gradual change here. Canis lupus arctos to Canis lupus familiaris.

4. The finches of the Galapagos are more than enough evidence of the natural selection of their beaks to different purposes. Good enough for Darwin; good enough for your argument.

You will get more ammo here, but go here for even more.

http://www.talkorigins.org

Answer 2

1. I assume you mean nonconstancy OVER TIME. (If you mean *variation* ... the fact that individuals of a species are not identical ... then this is trivial to show just looking at the range of characteristics of human beings, and you can move the following examples down to #3.)

Examples:
a) Every time you get a new flu shot, it's because there is nonconstancy in the flu viruses. This year's flu viruses are descendants of last year's flu viruses ... but they are different.

b) Through selective breeding, we can *accelerate* the nonconstancy of a species. We can, over time, breed a dairy goat to have a straighter back, stronger legs, and a better udder. Your friend will counter argue that this is artificial selection, not natural selection, but the point is that the nonconstancy (change) *itself* is part of the species. Selective breeding accelerates this process, it does not create it.

c) Humans are taller now than they were even 500 years ago. Go to museums and look at clothing and suits of armor from that time.

2) Every single species is the result of a branching. This is a key point often misunderstood by many people. Evolution is not just a chain. A species doesn't just "become" another species. A species splits into two species.

Here is a site with many documented examples of speciation by branching ... examples documented in the lab and in nature:
http://www.talkorigins.org/faqs/faq-speciation.html

3. See 1 (what's the difference between "nonconstancy" and "change"?).

4. One of the clearest examples is the flu virus (see 1a). The very reason we need a different flu shot every year is that "survival of the fittest" applies to viruses. Those that have some mutation that makes them resistant to last year's flu shot survive better than those who are not resistant. This means that this mutation propagates into the population better. This is why we need a new shot next year.

Answer 3

Hope this helps...two islands, each with lizards...they put a lizard eating animal on the island with lizards, and leave the others by themselves.
The lizards on the 1st island evolved and have bigger legs to climb trees and escape that predator.