Natural Selection Explanation HONORS NINTH GRADE SCIENCE Natural

Natural Selection Explanation HONORS NINTH GRADE SCIENCE

Natural Selection Darwin’s Mechanism for Evolution 1. Overproduction 2. Inherited variation 3. Struggle to survive 4. Successful reproduction 5. Adaptation of the species

All species over reproduce, with variations - total of alleles (variations) in a population is the “gene pool” -What is the allele frequency for feather color for this gene pool?

2. Inherited Variations come from mutation and random mating -Mutation: Changes in DNA ****(Darwin was missing this) -Random mating: mixing genes in reproduction Most birds are blue Sometimes, one is born green Sometimes, one is born blueishgreen

3. Struggle to Survive -Organisms compete for resources (food, shelter, mates, etc. ) -Those better suited, survive Most birds are blue Sometimes, one is born green Sometimes, one is born blueishgreen

The birds face the challenge of blending in to survive.

Ugh!, so full… Only some will survive and have the opportunity to pass on their successful genes. Ø Blue-green birds stand out more Ø Blue-green birds are eaten EEP !

4. Successful Reproduction Successful traits are passed to the next generation -Results in more organisms with the successful trait -Fewer organisms with the less successful trait(s) How has the allele frequency changed in this population? This is evolution!

5. Adaptation of the Species Adaptation: process by which a species becomes better suited to its environment ? Hee, hee…