Chapters 24, 40-42 Flashcards
(35 cards)
phylum chordate requirements
- notochord (rod of stiffened tissue)
- tubular, dorsal nerve cord
- gill slits across wall of pharynx
- tail extending past the anus
Filter-feeders and jawless fish
tunicates [brain]
lancelets [head]
hagfish [vertebrae]
lamprey
Jawed fish
sharks/rays [lungs] ray-finned fish [lobed fins] lobe-finned fish
amphibians, reptiles, & mammals
amphibians/terrest. tetrapods [amniotic eggs] reptiles/amniotes [milk] mammals/endotherm
amphibian (2 pairs of limbs) types
frog/toad
salamander
caecilian
Reptiles (can fertilize internally)
turtles, lizards, tuataras, snakes, crocodilians (4-chambered heart)
- live away from water
- amniotic egg, w/ shell-housing embryo in amnion
Birds (characteristics)
feathers on airfoils/wings,
light bones,
endothermic w/ high metab, amniotic eggs
Mammalian characteristics
hair/fur (insulation), mammary glands
- prevent overheating w/ sweat glands & evaporation
Mammalian types
monotremes (egg laying)
marsupials (pouched)
eutherians (placental)
population ecology
changes in population size and factors that regulate populations over time
population
localized group of individuals of a species
population size
of individuals that actually or potentially contribute to gene pool
population density
of indiv. of a species per unit area or habitat volume
population distribution (dispersion pattern)
general pattern in which indiv. are dispersed in a specific area
- clumped (most common), uniform, or random
population size estimates
quadrat sample plots (sampling areas of same size/shape); plants (stay put)
capture-recapture:
(marked# @2) = (marked# @1)
(total captured @2) (total pop. size)
zero population growth
interval when # of births is balanced by = # deaths
population size & growth
how to gain/lose indiv: immigration/emigration, migration
growth rate (G)
r x n
= (per capita growth rate) x (# indiv)
= (birth - death rate) x (# indiv)
Exponential growth model
population size increases in exact proportion of its total energy in each successive time interval
logistic growth model
idealized population growth slowed by limiting factors as pop. size increases
density indep: e.g. weather on rampage
density dep: limiting factors (competition for resources, disease)
carrying capacity (K)
max # of indiv. of population that an environment can sustain indefinitely
G = (r_max)(N)(K-N)/K
proportion of un-wasted resources
Survivorship curves
I: high until late in life; few offspring
II: relatively constant death rate
III: high death rate early in life
TFR
total fertility rate
avg # of children born of a population during reproductive years
biotic potential
max reproductive capacity under ideal conditions
