ecol midterm 3

defining features of animals

1. heterotrophs

2. lack an cell wall but have an ECM

3. multicellular

4. can move on their own accord

5. all cells have neurons that send chemical messages throughout body

intraspecific competition

same species (mates, space)

interspecific competition

different species (space, water)

niche

all the biotic and abiotic conditions and what the organism does its role in that area such as (saguaro:moisture, temperature, pollinators, nurse plants)

fundamental niche

could potentially occupy

realized niche

subset it actually occupies

pollination

transfer of pollen from male part to female part of a flower; needed before fertilization.

pollination syndrome

suite of floral traits matched to a pollinator type.

bee flower

day; yellow/blue/purple + UV patterns; light sweet scent; pollen and nectar.

butterfly flower

day; red/orange; light sweet scent; pollen and nectar.

fly flower (carrion/dung flies)

day and night; purplish-brown or greenish; strong decaying-protein smell; NO reward.

moth flower

night; white/pale; strong scent; pollen and nectar.

bat flower

night; dull white/green; strong fermented smell; ample nectar.

bird flower

day; red/orange; little to no scent; nectar.

n-fixing bacteria mutualism

plant gives organic carbon; bacteria give fixed nitrogen in root nodules (legumes).

mycorrhizal fungi mutualism

arbuscules form inside roots (big surface area). Fungus gives water + nutrients (esp. phosphorus); plant gives sugars.

nutrition

photosynthetic products (corals + dinoflagellates) and chemosynthetic products (e.g., N-fixation). also digestion

defense

pathogen prevention

communication

bioluminescence, where bacteria are contained in light organs

dispersion

moving the partner around (e.g., remoras hitching a ride on sharks)

functions of mutualism

nutrition, dispersion, communication,defense

antagonism

one does worse, one does better. four forms: predation, parasitism, herbivory, pathogens

predation

lure, capture, digest prey for nutrients; usually in nutrient-poor habitats (sundew, pitcher plants, venus fly trap).

herbivory

reduced apparency (stone plants blend in)

structural (thorns, spines, trichomes)

chemical (secondary metabolites)

secondary metabolites

Specialized compounds not part of basic metabolism (photosynthesis, etc.). Defense chemicals; humans use caffeine and nicotine.

parasites

use modified roots to take nutrients from a host.

pathogens

live inside hosts and cause disease: viruses, bacteria, fungi, parasites.

commensalism

+/0: one benefits, one unaffected

ammensalism

–/0: one harmed, one unaffected (many human–wildlife interactions)

advantages of bilateral symmetry

front/back and top/bottom, with a head

sensory organs concentrated at the front

goes with a CNS and brain

mobile animals moving forward

why was the coelom important?

cushions organs from muscle deformation

simple circulatory system

hydrostatic skeleton (earthworms)

organs grow independently of body wall

longer, coiled gut (human intestine ~21 ft)

heartbeat doesn’t warp body surface

human liver fluke

in platyhelminthes, flatworm parasite that must pass through two other hosts to finish its life cycle.

schistosoma life cycle

1) Eggs shed in human feces into water

2) Eggs hatch, infect snails

3) Snails shed a swimming stage

4) Burrows into human skin, infects organs, reproduces

four levels of analysis

mechanism, development, function, evolution

mechanism

the physiological or neurological basis: how does it work

development

the role of age and experience: how does it develop? Instinct or learned?

function

the adaptive value: why has natural selection favored this behavior?

evolution

the evolutionary history: where did it come from in this group?