Lecture 15-16 Niche, Life History, & Plant Functional Types

Study Guide

Lecture 15-16 – Niche, Life History, & Plant Functional Types

Be able to define “niche” and be familiar with how this term has evolved from the early work of Grinnell and Elton, to the more recent work of Hutchinson.

Be able to define the difference between a “fundamental niche” and “realized niche.”

Be able to relate a “tolerance diagram” (e.g. figure 5.8) or “distribution diagram” (e.g. fig. 10.17 and 10.18) to the niche concept.

Be able to provide examples of how both biotic and abiotic factors can help determine a species’ niche.

Be able to provide and discuss examples where ecologists have attempted to define or measure a species’ niche, and understand why a complete definition may be impossible.

Understand how the niche concept can relate to speciation (e.g. Galapagos finches).

Know that we have several other terms that are closely related to niche, including “guild” and “functional type” and be able to define these terms.

Know that niches can change as conditions change and species evolve in response. Be able to provide an example.

Be able to relate the concept of natural variation (e.g. in seed size and shape) to the term “niche” and relate concepts.

Understand how tradeoffs exist (optimality theory) between factors (e.g. seed size and number) that can help explain variation in nature.

Be able to provide and discuss examples of ways that we sometimes categorize organisms according to variation in traits (e.g. seed size), and how this might relate to ecological theory.

For example, be able to explain potential evolutionary advantages and disadvantages for being big, small, etc. (e.g. consider the seed size example). Be able to relate these patterns to ecological theory (e.g. optimality theory or life history/functional type theory).

Be able to define “life history” and understand examples of various life history schemes that have been proposed:

r and K selection (MacArthur & Wilson)

Plant strategies (Grime)

Opportunistic, equilibrium, and periodic (Winemiller & Rose)

Reproductive effort, offspring size, and benefit-cost ratio (Charnov) In particular, be very familiar with the first two schemes (r-K selection and plant strategies) and be able to provide examples.

Why have ecologists derived different schemes? In other words, why haven’t all ecologists agreed on a single life history scheme for all organisms?

Read Lavorel et al. (1997) on Plant Functional Classifications, TREE 12:474-478 (on web site) and be able to discuss the major concepts in that article.

Be able to define “plant functional types.” Why have ecologists developed concepts of “plant functional types?” In other words, why isn’t the “species” concept adequate?

Be familiar with common applications of “functional type” classifications, e.g. in global change research, disturbance ecology, and in Dynamic Global Vegetation Models.

What factors or concepts can be used to define functional types? Why is there no single definition of plant functional type?

Be able to provide examples of plant functional types as presented in lecture.

Understand how remote sensing is being used to understand the distribution and dynamics of plant functional types.