Evolution Flashcards
Evolution
Any change in heritable traits within a population across generations
Converge
when two species with different ancestral origins develop similar characteristics,
Diverge
Occurs when two groups of the same species evolve different traits within those groups in order to accommodate for differing environmental and social pressures.
Key factor of evolution
Reproduction
Homologus
Share a common ancestral trait
Transmutation of species
That species could change over time to produce new species and were not fixed and unchanging
Species
Members of the same species are able to reproduce to create fertile viable offspring
Hominin
hominin refers to various human species and their extinct close relatives that could walk erect on their hind legs
Concept of natural selection
The concept that species can change and give rise over time to new forms is known as evolution.
Natural selection
Natural Selection is tied to reproduction, those individuals who are most suited to their environment are more likely to survive and therefore more likely to reproduce.
Darwin-Wallace view
The theory asserted that individual organisms do not evolve in their lifetimes but that evolutionary change occurs over several generations in populations.
Evidence for evolution
Geological
Fossil record
Biogeography
Fossil
Fossils are the preserved remains, impressions or traces of organisms found in rocks of different ages
Biogeography
Biogeography is the study of the geographical distribution of fossils and living species.
Principle of Superposition
This principle states that, for rock layers or strata, the oldest stratum is at the bottom and progressively younger layers lie above
Analogous trait
Traits common to species but which have independently evolutionary origins
Characteristics of mammal
Thee bones in middle ear
Fur or hair on body surface
Teeth comprising of molars, pre-molars, incisors and canines
Milk producing mammary gland
Types of mammals
Monotreme
Placental
Marsupial
Oldest hominin fossils
7 million years ago in africa
Characteristics of australopithecus
Big teeth, small brain, heavy brow ridge, heavy skull, Male: sagittal crest
Sagittal crest purpose
Connection of jaw muscles
Trends in hominin evolution
Enlargement of brain the reduction of tooth size
the shortening of the face.
the reduction in the size of the face
The increasing of the jaw angle and the flattening of the face
Primate
any mammal of the group that includes lemurs, lorises, tarsiers, monkeys, apes, and humans.
Dna mutation
Errors can occur which modify DNA code
DNA mutation effect
Source of evolution, cold produce an advantageous characteristic and pass on the trait to future generations
