Can someone please define these terms: ?

Question

I actually searched and wrote down all of the definitions to these words, but this Theory of Evolution by Natural Selection lesson that I'm studying is really, really confusing me. Can someone try their best to explain these words to me SIMPLY... Thanks!

- Species

- Descent of Modification

- Evolution

- Natural Selection

- Population

- Artificial Selection

Some of these words are connected. ... I really enjoyed reading about The Cell Theory more than this stuff. = )

Answer 1

Evolution by natural selection should not be very confusing at all.  It is very simple.  It has the following elements:  (1)  organisms have a means of passing on information to the next generation and this is the DNA found in cells; (2) this information can be changed by random mutations; (3) changes in the DNA cause changes in the organisms; (4) these changes in the DNA may change the organism's ability to survive in a particular environment and pass on these changes to the next generation of fertile offspring; and (5) those changes that increase the chances of fertile offspring will become part genome of the surviving members of the species.  This is evolution by natural selection.

Species:  a classification of organisms based on the similarity of genome, similarity of the structure or the capability of interbreeding of organisms.  That is, members of the same species have similar genes, they look alike and they interbreed.  

Descent of Modification:  The changes in DNA that increase the probability of fertile offspring are more likely to be passed on to the next generation.

Evolution:  The changes in the genomes of species.

Natural selection:  The process of the changes of the genomes of species.

Population:  The number of individuals of a species.

Artificial selection:  The purposeful breeding of individuals, especially as it relates to agriculture and sexual selection.