Studied by 18 peopleextinct
describes a species that has compleatly disappeared from earth
adaptation
a structure behaviour or physiological process that helps an organism survive and reproduce in a particular environment
mimicry
a structural adaptation in which a harmless species resembles a harmful species in coloration or structure
variation
differences
mutation
any event that changes genetic structure; any alteration in the inherited nucleic acid sequence of the genotype of an organism
selective advantage
genetic advantage that improves an organisms chance of survival, usually in a changing advantage
natural selection
the process by which characteristics of a population change over many generations as organisms with heritable traits survive and reproduce, passing their traits to offspring
selective pressure
environmental conditions that select for certain characteristics of individuals and select against other characteristics
fitness
the relative contribution an individual makes to the next generation by producing offspring that will survive long enough to reproduce
artificial selection
selective pressure exerted by humans on populations in order to improve or modify particular desirable traits
biotechnology
the use of technology and organisms to produce useful products
monoculture
the cultivation of a single crop
paleontology
the study of aincent life through the examination of fossils
catastrophism
the idea that catastrophies such as floods, diseases, and droughts periodically destroyed species living in a particular region, allowing species from neighbouring regions to repopulate the area
uniformitaeianism
Charles Leyll's throry that geological processes operated at the same rates in the past as they do today
Georges-Lewis Leclarc, Comte de Bouffon
noted similarities between humans & apes
earth had to be older than 6000 years
Mary Anning
Family collected fossils
Helped discover the first specimens of an ichthyosaurus and plesiosaur
Her findings, contributions and knowledge were belittled because she was not formally educated and a female
Georges Cuiver
Founded vertebrate paleontology
Developed the ability to reconstruct organisms from individual parts based on patterns and proportions
Confirmed Anning’s fossils as genuine
Didn’t believe that lifeforms could evolve
From his comparative studies of mummified cats and modern cats (they were the same)
Established extinction as a fact
Mass extinction
50% of all species become extinct in a short time period ~ 2 million years
Charles Lyell
Rejected catastrophism
Rock cycle was driven by subterranean heat
Theory of uniformitarianism
Geological processes are slow and continuous, not catastrophic and they occur at a constant rate
Over long periods substantial change may occur
It works too slowly for us to perceive
Stabilizing selection
natural selection that favours the intermediate phenotypes and acts against extreme variants
Disruptive selection
natural selection that favours the extremes of a range of phenotypes rather than intermediate phenotypes; this type of selection can result in the elimination of intermediate phenotypes
directional selection
natural selection that favours the phenotyoes at one extreme over another, resulting in the distribution curve of phenotypes shifting in the direction of that extreme
inheritance of acquited characteristics
the idea that characteristics acquired during an organism's lifetime can be passed on to its offspring
theory of evolution by natural selection
a theory explaining how life las changed, and continues to change, during earths history
evolution
the process of genetic change in a population over time
Survival of the fittest
the idea that the organisms that are the fittest leave the most offspring, so those organisms win the struggle for survival
descent with modification
Darwins theory that natural selection does not deomonstrate progress, but merely results from a species ability to survive local conditions at a specific time
fossil record
the remains and traces of past life that are found in sedimentart rock, it reveals the history of life on earth and the kinds of organisms that were alive in the past
transitional fossil
a fossil that shows intermediary links between groups of organisms and shares characteristics common to two now seperate groups
vestigial structure
a structure that is a reduced version of a structure that was functional in the organism's anscestors
biogeography
the study of the past and present geographical distribution of species populations
homologous structures
structures that have similar structural elements and origin but may have a different function
analogous structures
structures of organisms that do not have a common evolutionary origin but perform similar functions
embryology
a branch of science that is related to the formation, growth, and development of embryo
gene flow
the net movement of alleles from one population to another due to the migration of individuals
non-random mating
mating among individuals on the basis of mate selection for a particular phenotype or due to inbreeding
genetic drift
the change in frequencies of alleles due to chance events in a breeding population
founder effect
a change in a gene pool that occurs when a few individuals start a new isolated population
bottleneck effect
changes in gene distribution that result from a rapid decrease in population size
Note
Flashcard