5.1 EVOLUTION AND BIODIVERSITY Flashcards
EVOLUTION
cumulative change in the heritable characteristics of a population
CUMULATIVE CHANGE
small change over many generations
HERITABLE CHARACTERISTICS
gene controlled factor
these traits cannot be acquired over a lifetime
they are traits or alleles in an organism’s DNA
EVIDENCE OF EVOLUTION
fossil records
homologous structure
vestigial structure: appendix
selective breeding
comparative DNA
observable changes
FOSSIL RECORDS
show the gradual change of a species over time
FOSSILS
are preserved remains of animals, plants and other organisms from the past
FOSSIL RECORD TIMELINE
bacteria/ algae: oldest
shelled animals/ trilobites
dinosaurs/ early reptiles
birds and mammals
SELECTIVE BREEDING
breeding plants and animals for a specific genetic trait
SELECTIVE BREEDING AS EVIDENCE OF EVOLUTION
shows a good record of recent changes in genetic characteristics over a few dozen generations that man has selected to breed
SELECTIVE BREEDING EXAMPLES
chickens that produce more eggs /cows that produce more milk
are selected to breed
hopefully passing these traits onto next generations
evolution of domesticated dogs
HOMOLOGOUS STRUCTURES
common internal structures that are similar in seemingly dissimilar ways that have evolved from a common ancestor
similar in shape in different types of organisms
POPULATION
not an individual
SELECTIVE BREEDING AKA
artificial selection
COMPARATIVE ANATOMY
structures or anatomical features having similar basic structure as in other species= homologous
HOMOLOGOUS STRUCTURE EXAMPLE
pentadactyl limb
5 digit limb found in animals
even though the shape, size and function of this structure vary between species, the general structure and position is the same
