Evolution CH16-17

what it is and how it works

biogeography

biology + geography. Species that live in similar environments tend to have similar characteristics, even if they're from completely different continents

natural selection

nature encourages certain traits in living organisms that are more beneficial for that environment

fitness

how well a species is suited for a particular environment

adaptation

process of a species becoming better suited for a particular environment

low fitness

species not well adapted to their environment, less likely to survive to reproduce

high fitness

species has adaptive traits best for its environment

evolution

a process of gradual change that takes place over many generations, during which species of animals, plants, or insects slowly change some of their physical characteristics

gene pool

Pool of genetic resources, all alleles of all genes in a population

speciation

The formation of new and distinct species during evolution

fossils

remains or traces of organisms that lived long ago

fossil record

Allows us to compare fossils of ancient organisms to modern organisms alive today

transitional fossils

shows intermediate species. Can see where an ancient species was slowly becoming a modern species we see today

phylogenetic tree

a diagram that depicts the lines of evolutionary descent of different species, organisms, or genes from a common ancestor.

microevolution

Evolutionary change within a species over a short amount of time. Typically see this with insects, bacteria, viruses

macroevolution

large scale changes in a species over time .

four principles of evolution

variation in traits, inheritance of traits, selection fo traits, time