Conservation Biology Twu Test 1Chapter 3

Front 1

One of the major components of biological diversity is...

Back 1

the abundance and distribuation of species throughout the world.

pg. 51

Front 2

The most species-rich environments appear to be...

Back 2

tropical rain forests and deciduous forests, coral reefs, large tropical lakes, dn perhaps the deep sea

pg 51

Front 3

The frequency of fire in this area may favor rapid speciation and prevent the domination of just a few species.

Back 3

Temperate Communities

pg. 52

Front 4

Species richness is the greatest in...

Back 4

Tropical environments.

pg. 52

Front 5

Even though the world's tropical forests occupy only ___% of the land area, they contain ___% of the world's species, and ___% of the world's birds.

Back 5

7
50
30

pg. 53

Front 6

Water in the reef ecosystem allows sunlight to penetrate deeply so that...

Back 6

high levels of photosynthesis occur in the algae that love mutualistically inside the coral.

pg. 53

Front 7

High species richness in coral reefs can be due to...

Back 7

1. Extensive niche specialization among coral species
2. Adaptations to varying levels of disturbance

pg. 54

Front 8

The largest coral reef is...

Back 8

Australia's Great Barrier Reef

pg. 54

Front 9

Only isolated islands have numerous restricted-range ______ species.

Back 9

endemic- found in a particular location and nowhere else

pg. 54

Front 10

In terrestrial communities, the most species are in...

Back 10

hot, rainy, low-land areas.

pg. 54

Front 11

Species diveristy is greatest at _____ habitats.

Back 11

intermediate- not the wettest or driest, not great depths or close to the surface...

pg. 55

Front 12

Environmental variation allows for...

Back 12

genetic isolation, local adaptation, and speciation to occur.

pg. 55

Front 13

High species diverisity in the tropics may be due to...

Back 13

greater productivity and stability, warmer temperatures, and more niche specialization, allowing many species to flourish and co-exist.

pg. 57

Front 14

5 theories to why there is greater diversity of species in the tropics...

Back 14

1. Tropical regions receive more solar radiation and have abundant rainfall- the high productivity results in a greater resource base that can support a wider range of species.
2. Uninterrupted- a relatively more stable climate allowed a greater degree of evolutionary specialization and local adaptation to occur in tropical areas.
3. Warm temperatures and high humidity in many tropical areas provide favorable condition for the growth and survival of many species- suggests that adapations to cold do not evolve easily or quickly.
4. niche specialization- and no freezing weather in winter to reduce pest populations so parasites prevent any single species or group of species from dominating communities.
5. Large geographical area- the tropical areas N and S of the equator are next to each other, while the temperate areas outside the tropics are divided in two by the tropics themselves.

pg. 57

Front 15

There are between ___ and ___ million species, about ___ million described, and about ___ thousand new species described each year.

Back 15

5 million and 10 million
1.5 million
20 thousand

pg. 58

Front 16

New species are typically discovered when...

Back 16

taxonomists collect specimens while on field trips, can't identify it, create a new description, and give it a new scientific name.

pg. 58

Front 17

Recently discovered communities include:

Back 17

1. Diverse communites of animals, particularly insects, are adapted to living in he canopies of tropical trees
2. The floor of the deep sea has unique communities of bacteria and animals that grow around geothermal vents
3. The interior of leaves of healthy tropical trees has revealed an extraordinarily rich group of fungi, consisting of thousands of undescribed species.
4. The human body is populated by millions of viruses, bacteria, fungi, and mites.

pg. 61

Front 18

Large institutions and teams of scientist often undertake...

Back 18

biological surveys of entire countries or regions, which may involve decades
*specimen collection, identification of know species, descriptions of new species, publication

pg. 62

Front 19

The most diverse group of organisms appears to be the...

Back 19

insects.

pg. 63

Front 20

Back 20

Shaded areas in map at leaft were formerly covered with tropical forest. Smaller darker areas show where human activity has left forest intact.
About 40 percent of the world’s plant life occur within the tropical forests
About 30 percent of the world’s bird life occurs in the tropics

Front 21

Back 21

The Neotropics still has vast tracts of intact forest compared to the Paleotropical realm (Africa, Asia, Australia). Notice that the dark areas – intact forest – straddle the equator or fall within the tropics – (23°N and 23°S). Reefs are similarly inhabited, rich with species in the tropics.

Front 22

Back 22

Reef life in tropical marine waters occur where suitable substrate occurs within the photic zone. Estimates of species diversity in reefs suggests that species are less endemic and are more widely distributed than terrestrial forest species.

Front 23

Back 23

Patterns of Diversity:
*Variation in climate and environment – species richness increases with decreasing elevation, increasing solar radiation, and increasing precipitation (or intermediate levels of precipitation)
*Variation in topography, geological age and habitat size all correlate with increasing diversity

Front 24

Back 24

Reefs are distributed differently than terrestrial ecosystems: ocean currents provide a means of dispersing organisms. High vagility (dispersability) probably limits out-crossing and limits isolation, restricting speciation and the evolution of endemics.

Front 25

Back 25

Terrestrial mammals, trees and birds show a similar pattern of species richness with respect to latitude in North America. The suspected causes of tropical diversity being more deterministic than in temperate and polar regions:
*Tropics receive more solar energy, hence have a greater productivity which provides for a greater energy base than in temperate areas
*Large contiguous geographical area of tropics (?) may provide greater opportunity for speciation
*Long uninterrupted periods of climatic stability – no glaciation in the tropics
*Tropics are not exposed to extreme temperatures , e.g., year long frost free growing season
*Species interactions are constant and continuous promoting opportunities for speciation/diversification.

Front 26

Back 26

*Current knowledge of species in the biosphere is limited

*Only 1.5 million formal names (latin binomials) for organisms exist

*The majority of named organisms come from two different groups of organisms: insects and plants

Front 27

Back 27

The diagram at right is very important because it highlights the disparity between the known number of species and the estimated number of species for major groups of organisms.

This disparity is due to limited collection and study

Which groups have the greatest number of potentially undescribed species?

Front 28

Back 28

Description of new species is occurring all the time.
We discover new species and constantly add about 1-2 percent per year through focused study by trained taxonomists who are engaged in field work. We also add new species when detailed study of populations of existing species deem distinction based on details: micromorphological, physiological, genetic….
We encounter populations of living fossils: Wollemia pine discovered in Australia in 1994 was previously known from fossil pollen and leaves.
***A member of the recently described
Mantophasmatodea, from Namibia

Front 29

Back 29

Access to previously unstudied communities and ecosystems provides opportunity for discovery. The tropical canopy is just one of the areas that upon receiving attention has yielded novel species and understanding of community relations.
Other areas include the open ocean (a survey of the Sargasso Sea by C. Venter et al. [2004] discovered 148 new bacterial phylotypes from 1800 genomic species), bacterial communities residing at 2.8 km deep in the earth’s crust and deep sea hydrothermal vents

Front 30

Back 30

Estimating species number requires collecting describing and identifying specimens as well as attempts to estimate community diversity using such techniques as tree fogging:
One study focused on insect fauna in tropical tree canopies. If there are 55,000 species of tropical trees and lianas. On average, 9 species of specialized beetles feed only on one plant species’ canopy. This suggests that 400,000 to 500,000 species of canopy beetles exist in the tropics. If canopy beetles represent about 44 percent of all beetles, their may be as many as one million (1,125,000) beetle species. If beetles constitute about 20 percent of all insects, there may be 5 million (5,625,000) insects in tropical forests. These estimates are consistent with hypotheses of 5 to 10 million species on earth.

Front 31

Back 31

The cumulative percent of Chilean animals suggests that the conspicuous organisms were recognized early on, while less conspicuous species were enumerated much later.

Front 32

Back 32

Primack tries to recruit students to become taxonomists by showing how new species are potentially just under a rock