Isthmus of Panama Flashcards Preview

ENVR 202 pt. 2 > Isthmus of Panama > Flashcards

Flashcards in Isthmus of Panama Deck (21):
1

Pangea breakup

last continents to move NA and SA, change ocean currents- but ocean could still move between NA and SA- isthmus formation changed ocean

2

Isthmus formation

circulation of tropical warm water blocked, in Atlantic water deflected north- Gulf Stream; salinity of two oceans altered

3

Ocean Circulation

Driven by temperature and salinity differences- density differences; also impacted by trade winds and land masses

4

Water Density

warm and low salinity water less dense; warm water stays at surface; dense water stays deep- as density changes it rises/ falls in water column

5

Upwelling

water rising

6

downwelling

water falling

7

Gulf stream

formed with isthmus, impacts weather patterns in NA and Europe- brings heat

8

Biotic effects

barrier to marine; corridor for land; indirect effects of altering climate and changes in distribution, ecology

9

Marine species and barrier

isolation of populations, speciation; differences in marine environments on either side

10

Pacific Marine Environment

Deep; high production; low construction- deep basin, winds push water away from land, upwelling of nutrients ;, upwelling of cold water; greater nutrients favors organisms with faster lifecycles, deep water does not favor photosynthesis

11

Production

growth and multiplication

12

construction

development of more permanent biological materials (like coral)

13

Caribbean (Atlantic) Marine Environment

Shallow; low production; high construction- shallow waters support growth of photosynthetic organism, no upwelling, favors slower growing organisms with low nutrient input- biotic interactions as opposed to nutrient availability

14

Terrestrial species corridor

Similar ecological niches on both continents- can't have exact same niche (can't have more than one apex predator), almost entirely different species before connection (convergent evolution), species mix- only good dispersers and can survive dry environment

15

convergent evolution

unrelated species evolve similar traits due to similar environmental and ecological conditions

16

Convergent mammals

marsupials vs. placental mammals

17

Heralds

south moves up (sloths), north moves down (raccoons)

18

Legions of the north

lots move south, those that moved south persist in south

19

legions of the south

idk not really important basically most immigration from north to south- outcompete marsupials

20

Changing climates

mountain formation and rain shadow, ecological barrier

21

Human changes

panama canal maybe some species exchange across ocean