important concepts exam 1 Flashcards
what is evolution?
descent with modification, all organisms are related through descent from an ancestor that lived in the remote past
what are fossils?
remains or traces of organisms from which the past, usually found in sedimentary rock
what is strata?
layers of sediment that appears in layers
what are ancestral species?
found deeper in lower layers
what are derived species?
fossils found in the upper layers
what are adaptions?
are the traits possessed by species
what are extinct species?
species that are no longer alive
what are extant species?
species that are still living (in existence)
what is artificial selection?
Darwin noted that humans have been modified other species by selecting and breeding individuals with desired traits (human interruptions to natural selection)
what are darwin’s observations?
- species vary in traits, species populate at a high rate more than the environment can handle which leads to death of those who cannot survive
Darwins Inferences
- those who inherit good traits will have a higher chance of surviving & the unequal ability of individuals to survive will fill the environment with favorable traits
what is direct observation of evolutionary change?
observing natural selection over a period of time, COVID evolving each flu season
what is homology?
similarity resulting from a common ancestry
what is a homologous structure?
anatomical resemblances that variations on a structural theme present in a common species
what are vestigial structures?
remnants of features that serve important functions in the organisms ancestors
