Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
30 Cards in this Set
- Front
- Back
macroevolution
|
The large-scale patterns, trends, and rates of change among families and other more inclusive groups of species.
|
|
speciation
|
starts when a population becomes reproductively isolated from others of the species and ends with new species.
|
|
biological species concept
|
a species is one or more groups of individuals that can interbreed, produce fertile offspring, and are isolated from other groups.
|
|
prezygotic isolation mechanisms
|
reproductive isolating mechanisms; behavioral, temporal, mechanical, ecological, and gametic mortality.
|
|
Allopatric speciation
|
speciation in geographically isolated populations. some sort of barrier arises and prebents gene flow. effectiveness of barrier varies with species. Ex:Isthmus bridge of panama
Mississippi River |
|
postzygotic isolation mechanisms
|
unsuitable interactions of genes can lead to: death, sterility, weak hybrids.
Ex: mules, ligers |
|
Sympatric speciation
|
species form within the home range of the parent species. no physical barrier. Ex: Africa Cichilds
|
|
Parapatric speciation
|
Neighboring populaitons become distinct species while maintain contact along a common border
|
|
Community structure
|
the patterns of species abundances, species interactions, and local biodiversity for a given community. Ex: new guinea pigeons, fire ants
|
|
habitat
|
a place where each organism lives.
|
|
community
|
all the populations that live together in a habitat.
|
|
niche
|
Sum of activities and relationships in which a species engages to secure and use resources necessary for survival and reproduction.
|
|
Mutualism
|
both species benefits.
helpful interaction: not vital ex: ants and aphids |
|
commensalism
|
helps one species and has little to no affect on the other
|
|
parasitism
|
both benefit one species at a cost to another
|
|
interspecific competition (two types)
|
competition between (among) individuals of the same species. (very intense)
|
|
intraspecific competition
|
competition between populations of different species. (less intense)
|
|
competitive exclusion
|
when two species compete for identical resources. one will be more successful and will eventually eliminate the other
|
|
Realized niche
|
niche a species actually occupies. shifts over time. ex: barnacles in tide pools
|
|
fundamental niche
|
theoretical niche occupied in the absence of any competing species
|
|
interspecific competition:
1. Interference competition |
one species controls or blocks access of another species to some resource. Ex: chipmunks, broadtail and rufous hummingbirds.
|
|
interspecific competition:
2. exploitative competition |
species have equal access to required but limited resources. one species is better at using the resource.
|
|
resource partitioning
|
a subdividing of some category of similar resources. allows competing species to coexist. ex: pigeons of new guinea, three annual plants.
|
|
coevolution
|
species evolve jointly as their close ecological interaction exerts selection pressure on each other over generation. ex: snail shells thickened... crab claws become larger
|
|
factors shaping community
|
climate and topography, available foods and resources, adaptations of species in community, species interactions, arrival and disappearance of species, physical disturbances. ex: rainforest vs. arctic
|
|
prey defenses
|
camouflage: blending in w/the surroundings, mimicry: copying another species, often distasteful or toxic, and chemical defenses.
|
|
Population distribution type 1
|
typical of human populations where health care is good. animals that have few young and extended parental care. Ex: elephants
|
|
populaiton distribution type 2
|
Fairly constant death rate at all ages. Lizards, small mammals, and large birds.
|
|
population distribution type 3
|
death rate is highest early in life. species that produce many small offspring and do little parenting. ex: sea turtles, fish, star fish
|
|
Fertility rates
|
is the average number of children born to a woman. by 2050 it may peak at 9 bill.
|