Evolution Exam 2 Chapter 8 And Ecology

Front 1

Define fundamental ecological niche.

Back 1

Set of all environmental conditions in which a species can maintain a stable population size

Front 2

Define potential niche.

Back 2

Overlap of fundamenta niche and realized environmental space

Front 3

Define realized ecological niche

Back 3

Range of environmental conditions that a species actually occupies

Front 4

What are the problems with defining the different types of niches?

Back 4

It is difficult to identify all environmental factors that might affect population growth, especially because some borders are thought to be set by competition with other species (ex. honeyeaters)

Front 5

Define phylogenetic niche conservation

Back 5

Related species often have ecological requirements presumably derived from a common ancestor

Front 6

Define the Latitudinal diversity gradient

Back 6

Most taxa are far more diverse in tropic regions. Why? Better climate, more competition = adaptation to tiny niches. Tropical areas so much older = organisms have had more time to evolve and diverge

Front 7

What are the 3 hypotheses about the latitudinal diversity gradient. Explain each

Back 7

1. Ecololigcal hypothesis: high because of abundant solar energy or fine partitioning of resources among species
2. Diversification rate hypothesis: rate of increase in dversity has been greater in tropics for a long time becuase of higher origination rate, lower extinction rate, or both
3. Time and area hypothesis: most lineages have originated in the tropical environment throughout the Cenozoic era and even before, bcuz Earth was warmer than today. Most linages are adapted from tropical climates.