How does genetics effect the selection of animals?

Question

Thank you in advance, my daughter forgot her book and I am useless when it comes to this.

Answer 1

First of all, when genes are passed from one generation to the other, complete accuracy is not present and thus the offspring is slightly different from the other.

Secondly, when a species adapts, it only adapts to a SPECIFIC environment, not to every single environment in the world. That's why death is still inevitable.

Hope you get the message. :| :)

Answer 2

Genetics effects the selection of animals because those animals that are more fit, or capable of surviving in their environment are going to have a great probability of passing on their genes to the next generation.  Here's an example.  When a nest full of caterpillars hatches they race towards the leaves for food, the ones that are faster will be able to get farther and therefore get more food then those that move slowly which will only be able to get to the leaves after others have eaten them.  The fast ones will then have a greater chance of surviving and passing on their genes so that the next generation of caterpillars will have their gene to move fast to get to the food, thus selecting for the caterpillars that have the gene to move faster.  I hope that this helps and makes sense!