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Flashcards in lec 17 Deck (46):
1

Area-hypothesis (_________): _________
Considerable evidence supports this at _________
Such as the ___________ which is the______

- species area effect
- Larger areas have more species because they can support larger populations and a greater range of habitats
- regional scales
- equatorial region
- largest climatically similar region in world

2

tundra biome is the ________
but has _________

- second largest terrestrial region
- low species richness

3

That open ocean has
but has

- the largest area of any marine system, and the largest volume of any habitat
- fewer species than tropical surface waters

4

productivity hypothesis: _________
An increase in plant biomass _________
Evidence for this hypothesis is

- greater production of plants results in greater overall species richness
- support more herbivores and hence more predators, parasites and scavenger species
- Bird and mammal species richness increases with productivity in N.A.

5

metabolic theory
accumulating theoretical and empirical studies suggest that the single most important factor

- ecological and evolutionary rates are temperature dependent
- kinetics

6

Succession

temporal change in community structure at a given location

7

Steps in abandoning cropland going through succession

____________ colonize followed by _______
over time _________ are replaced by _______
eventually forming a _________
_____ begin to occupy the ________
Eventually _____________ dominate the landscape

- grasses and weedy herbaceous plants colonize
- shrubs
- shrubs are
- conopy forest
- hardwood trees
- the understory
- deciduous hardwoods

8

Each of the stages in succession is called a _______
a point on the ______________
These stages can often be recognized as _______
with ____________

Stages can be ________ and may last ______

- seral stage
- continuum of vegetation through time
- distinct communities
- characteristic structure and species composition

- missed
- years or decades

9

Succession

begins with a disturbance
- seen in both terrestrial and aquatic environments

10

Succession begin with _________
A force that __________
It may be
They all exhibit

- a disturbance
- alters a biological community and remoes or destroys organisms
- storms, fires, floods, drought or human caused
- different frequencies and intensities

11

Succession is seen in both

terrestrial and aquatic environments

12

pioneer species

early successional species
who are the initial colonists

13

pioneer species often have

- high growth rates
- smaller size
- a high degree of dispersal and colonization
- high rates of per captia population growth

14

Climax species

late successional species which arrive later

15

climax species often have

- longer lifespans
- a larger size
- lower rates of dispersal and colonization
- lower rates of per capita population growth
- the patterns of species replacement through time are not random

16

Succession types

primary succession and secondary succession

17

primary succession occurs at _______
This type of succession occurs in a

- a location that was not previously occupied by a community; a newly exposed surface,
- baron lifeless environment

18

secondary succession occurs at
this type of succession can build

a location that was previously occupied by a community and then underwent a disturbance that removed all or part of the existing community
- on the remainder of the previous community

19

sand dune

an inhospitable site that can undergo primary succession

20

sand is __________
unlike soil ________ it has

- a product of weathered rock deposited by wind and water
- minimal nutrients and ability to retain water

21

successional stages of sand dunes
__________ stabilize the dune with _________
Then _________ colonize
Subsequently ______ invade: first ________, then _____
Trees that ________________ rarely succeed the pines and oaks except in __________

During succession _________ can _____ making it more _____________

- pioneering species such as grasses
- extensize rhizomes
- mat forming shrubs
- trees
- pine(conifers)
- oak (hardwoods)
- more moisture
- depressions or other areas where moisture accumulates
- colonizing species
- change the environment
- hospitable for other species

22

fire is ___________ in many ecosystems
Some __________ require fire for ________

- a key and natural disturbance causing secondary succession
- coniferous trees
- reproduction

23

reasons to let the forests burn: ___________
Fire suppression in forests permits __________ which is very susceptible to

- major forest fires can be avoided by having frequent small fires
- the build up of dead wood
- burning, especially during lighting strikes during summer

24

many national parks conducted

controlled burns to maintain natural disturbance and succession and to prevent large and intense forest fires

25

equatorial region

largest climatically similar region in world

26

tundra

second largest terrestrial region, low species richness

27

open ocena

largest area of any marine system
- largest voluem of any habitat
- fewer species than tropical surface waters

28

productivity hypothesis

greater production of plants results in greater overall species richness

29

an increase in plant biomass

support more herbivores and hence more predators, parasites and scavenger species

30

metabolic theory

accumulating theoretical and empirical studies suggest that ht esingle most important factor is kinetics

31

Succession

temporal change in community structure at a given location

32

Steps in abandoning cropland going through succession

grasses and weedy herbaceous plants colonize, followed by shrubs
- over time shrubs are replaced by pine trees, eventually forming a conopy forest
- hardwood trees bein to occupy the understory
- eventually deciduous hardwoods dominatt he landscape

33

seral stage

a point on the continuum of vegetation through time
- can be recognized as distinct communites with characteristic structure and species composition

34

succession

begins with a disturbance
- seen in both terrestrial and aquatic environments

35

disturbance

a force that alters a biological community and remoes or destorys organisms
- may be storms, fires, floods, drought or human caused
- exhibit different frequencies and intensities

36

Succession types

primary succession and secondary succession

37

primary succession

occurs at a location that was not previously occupied by a community; a newly exposed surface, occurs in a baron lifeless environment

38

sand dune

is an inhospitable site that can undergo primary succession

39

many national parks conducted

controlled burns to maintain natural disturbance and succession and to prevent large and intense forest fires

40

ecosystem engineer

another type of keystone species that creates, modifies and maintains habitats

41

biological diversity

the variety or number of organisms that make up the community

42

species richness

total number of species in a community

43

species diversity

the number of species in a community relative to the number of individuals

44

Time hypothesis

Communites diversity or gain species with time

45

By the time hypothesis,
Temperate regions have less diversity because _______ and have only recently ___________
Species have not ______________ in temperate regions

- they are younger
- recovered from glaciation
- time to evolve and exploit regions

46

One would expect marine organisms to be able to rapidly _______________ after glaciation
But the richness of marine organisms follows the same ________

- recolonize the temperate and polar regions
- polar-equatorial species gradient