Chapter 1: Evolution Flashcards
Thomas Aquinas and Albertus Magnus
the two theologists who proposed “natural truth” and “revealed truth”
Roger Bacon
urged against religious dogma and told people to “look at the world”
Francis Bacon
advocated experimentalism as a way to verify and rigorously test all things
Nicklaus Copernicus
an astronomer who theorized that the earth revolves around the sun, not the other way around, like theologists believed
Galileo Galilei
an astronomer who supported the Copernican theory, and was placed under house arrest for 14 years because of it. He was also later forced to recant his scientific views.
Isaac Newton
the english physicist who discovered gravity
James Usher
an archbishop who declared that the earth was created in 4004 BC
catastrophism
the theory that the Earth’s landscape is shaped by global catastrophes
gradualism
the theory that the Earth’s geological features are a result of slow, continuous processes
uniformitariansim
the theory that geological processes have remained “uniform” throughout all of history. For example, the rate at which sedimentation occurs has remained constant over the Earth’s entire history.
biogeography
the study of the past and present distribution of individual species and entire communities
adaptation
a particularity of structure, physiology, or behavior that increases an organism’s chance of survival and reproductive success
niche
the role of a species in the community of which it is part. It is the sum of an organism’s adaptations, resources, and trophic interactions with other organisms.
natural selection
the differential reproductive success of members of a species
artificial selection
the process by which desirable traits are selectively bred in plants and animals
survival of the fittest
variations that provide the greatest survival and reproductive advantages will be propagated at a greater rate than variations that are disadvantageous
selective pressure
when an outside force affects the composition of a population by favoring certain traits over others
half-life
the number of years required for half of the isotope to decay into another, more stable, element
coevolution
the reciprocal evolution of two or more interacting populations
transition fossils
fossils of organisms that seem to present a direct lineage between ancestral and present-day organisms
cladogenesis
a pattern of change characterized by the branching of a lineage into different paths
mass extinction
where the number of taxonomic families drops sharply
phylogeny
the evolutionary history of a species or a group of related species
natural selection
the process by which favorable variations become more frequent in the gene pool
vestigial structures
structures that are present in an organism yet have no apparent function
homologous structures
equivalent structures between species with common ancestors
analogous structures
structures that have superficial and functional similarities, not because of common ancestry, but because of convergent evolution
convergent evolution
structures with similar functions arise separately in different species
species
a group of organisms that can breed with one another in a wild, free-ranging condition to produce fertile offspring
speciation
the process by which new species arise
adaptive radiation
the evolution of many related species from an ancestral species in a relatively short time. Can occur when the ancestral species exploits many new ecological niches.
prezygotic isolation
barriers to reproductive events that take place before fertilization
postzygotic isolation
barriers to reproduction that occur after fertilization has taken place
morphotype
different types of individuals of the same species in a population; a morph
allopatric speciation
a form of speciation that occurs when populations become geographically isolated from one another
selective pressure
an outside force that affects the composition of a population by favoring certain traits over others
theory
a comprehensive explanation based on a broad set of observations
hypothesis
a proposed explanation for an observation
the heterotroph hypothesis
attempts to explain how the first life on earth evolved
prokaryote
a one-celled organism that lacks a nuclear membrane, and can be divided into the subgroups bacteria and archaea
eukaryote
an organism that has a nuclear membrane in its cell
stromatolites
dome-shaped fossils of bacteria (prokaryotes) that are between 3.5 and 4 billion years old
reducing atmosphere
an atmospheric condition that lacks free oxygen, and may contain such reactive gases as hydrogen and/or carbon monoxide. The chemicals in this type of atmosphere can act as reducing agents—they donate electrons. This characteristic allows for the synthesis of organic molecules.
biotic
living organisms in the environment
abiotic
the nonliving environment
oxidizing atmosphere
an atmosphere that contains high amounts of oxygen
protobionts
aggregates of molecules that might have been precursors to cells
heterotroph
takes in materials and processes them
coacervates
aggregates of polymerized molecules, such as starches and proteins, that self-assemble
polymers
molecules made up of individual subunits bonded together to make one long chain
proteinoids
abiotically produced polypeptides
microspheres
formed when proteinoids self-assemble to surround water and exhibit some characteristics of a membrane
liposomes
a shell of lipids that self-assembles to surround water and molecules
ribozyme
an RNA molecule that can catalyze chemical reactions
nucleotides
subunits of RNA
catalyst
a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change
RNA
a polymer made up of subunits called nucleotides
