3 - Global diversity patterns

Question 1

Land sea diversity rule deterministic explanations

Answer 1

• Land more productive
• More difficult movement in water
• Greater habitat heterogeneity on land

Question 2

Heterogeneity

Answer 2

the quality or state of being diverse in character or content

Question 3

Land sea diversity rule evolutionary explanations

Answer 3

• More geographic isolation on land
• Reduced dispersal on land
• speciation / extinction
• Time
• Rates of transition between habitats
• Diversification within habitats

Question 4

Speciation

Answer 4

When a group within a species separates from other members of its species and develops its own unique characteristics

Question 5

Biodiversity hotspot

Answer 5

Regions that contain a high level of species diversity, many endemic species (species not found anywhere else in the world) and a significant number of threatened or endangered species.

Question 6

Biodiversity hotspots around the world

Answer 6

• Madagascar - world’s second-largest island after Indonesia and is over 150 million years old
• Brazil’s Atlantic Forest Region
• The California Floristic Province
• South Africa’s Cape Floristic Region
• The Philippines
• Thailand
• The Tropical Andes

Question 7

The latitudinal gradient of diversity

Answer 7

1. Richness increase at equator
2. Richness increases at low elevation, depth or aridity
3. Richness increase with an increase in topographic complexity

Question 8

Mid-domain effect

Answer 8

The hypothesis states that if the ranges of the species are randomly distributed within a bounded domain then more ranges will overlap near the middle of the domain than at the edges, and thus decreasing species richness will be observed from the mid-domain to the edges.

Question 9

Area theory

Answer 9

Larger habitat areas hold more species than smaller ones.
As one extends the sampled area, the total recorded species increases at a diminishing rate.

Question 10

The latitudinal gradient of diversity – the earth’s structure

Answer 10

1. Mid-domain effect
2. Area theory

Question 11

The latitudinal gradient of diversity – abiotic

Answer 11

3. Species-energy theory
4. Physiological tolerance
   hypothesis

Question 12

The latitudinal gradient of diversity – biotic

Answer 12

5. spatial heterogeneity theory
6. competition theory
7. enemies theory

Question 13

Species-energy theory

Answer 13

If energy has a causal relationship with richness, then species-energy theory implies that energy causes richness to increase in low-energy areas, energy has little effect in intermediate-energy areas, and energy depresses richness in the highest-energy areas.

Question 14

Physiological tolerance
hypothesis

Answer 14

Proposes that plant species richness is highest in warm and/or wet climates because a wider range of functional strategies can persist under such conditions.

Question 15

spatial heterogeneity theory

Answer 15

It refers to the uneven distribution of various concentrations of each species within an area.

Question 16

competition theory

Answer 16

Competition is a relationship between organisms that strive for the same resources in the same place.
Intraspecific competition occurs between members of the same species. It improves the species’ adaptations.
Interspecific competition occurs between members of different species.

Question 17

enemies theory

Answer 17

• The Enemy release hypothesis is the idea that invasive species are less impacted by enemies (e.g., herbivores) than native species, because in the new geographical location, the invasives species are freed from the parasites that kept their growth in check in their native environment.
  -Predicts a positive correlation between plant species richness and natural enemy abundance, which results in the regulation of herbivores at lower levels in diverse vegetation than in pure stands.

Question 18

Intraspecific competition

Answer 18

occurs between members of the same species. It improves the species’ adaptations.

Question 19

Interspecific competition

Answer 19

Occurs between members of different species.

Question 20

The latitudinal gradient of diversity – evolutionary

Answer 20

8. time/stability theory
9. tropical conservatism hypothesis
10. evolutionary
    speed theory

Question 21

Time/stability theory

Answer 21

!!!!

Question 22

tropical conservatism hypothesis (TCH)

Answer 22

tries to explain the generally observed latitudinal gradient of increasing species diversity towards the tropics.

Question 23

evolutionary speed theory (ESH)

Answer 23

Proposes a causal mechanism for the latitudinal diversity gradient — warmer temperatures lead to shorter generation times and increased mutation rates.

Question 24

Dimensions of diversity (local vs regional diversity patterns)

Answer 24

1. Scale
2. Grain
3. Latitudinal range
4. Global richness
5. Dispersal mode
6. Body mass
7. Thermoregulation
8. Trophic level
9. Longitude
10. Hemisphere
11. Realm