Chapter 22 Flashcards
evolution
descent with modification
-can be viewed as a pattern and a process
taxonomy
the branch of biology concerned with classifying organisms
who developed the binomial format for naming species?
carolus linnaeus
fossils
remains or traces of organisms from the past, usually found in sedimentary rock, which appears in layers or strata
in sedimentary rock where is the most recent fossils and where are the older fossils?
- younger fossils are more towards the top of the sedimentary rock
- older fossils are more towards the bottom of the sedimentary rock
paleontology
study of fossils
catastrophism
speculating that each boundary between strata represents a catasrophe
perceived changes in Earth’s surface can result from _______
slow continuous actions still operating today
uniformitarianism
the mechanisms of change are constant over time
what did Lamarck hypothesize?
species evolve through use and disuse of body parts and the inheritance of acquired characteristics
-not true
natural selection
the mechanism of descent with modification
- individuals with favorable inherited traits are more likely to survive and reproduce
- increases the adaptation of organisms to their environment over time
- if an environment changes over time, natural selection may result in adaptation to these new conditions and may give rise to new species
what is descent with modification?
the view that all organisms are related through descent from an ancestor that lived in the remote past
artificial selection
humans have modified other species by selecting and breeding individuals with desired traits
what are two important observations Darwin had?
1- members of a population often vary in their inherited traits
2-all species can produce more offspring than the environment can support, and many of these offspring fail to survive and reproduce
From the two observations Darwin had, what are his two inferences?
1-individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than other individuals
2-this unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations
if some heritable traits are advantageous, these will _____ in a population over time, and this will ______ the frequency of individuals with these traits
- accumulate
- increase
true or false:
individuals evolve
FALSE
-populations evolve over time
True or false:
natural selection can only increase or decrease heritable traits that vary in a population
TRUE
True or false:
Adaptation don’t vary with different environments
FALSE
adaptations vary with different environments
Can natural selection make up new traits?
no, it can only edit or select for traits already present in the population
homology
similarity resulting from common ancestry
homologous structures
anatomical resemblances that represent variations on a structural theme present in a common ancestor
comparative embryology
reveals anatomical homologies not visible in adult organsims
vestigial structures
remnants of features that served important functions in the organism’s ancestors
evolutionary trees
hypotheses about the relationships among different groups
convergent evolution
evolution of similar, or analogous, features in distantly related groups
when do analogous traits arise?
when groups independently adapt to similar environments in similar ways
does convergent evolution provide info about ancestry?
NO
Fossil record
provides evidence of the extinction of species, the origin of new groups, and changes within groups over time
biogeography
the geographic distribution of species, provides evidence of evolution
pangea
when earth’s continents were formerly united in a single large continent
endemic species
species that are not found anywhere else in the world
