Lecture 15: Movement and assembly of species (Exam 3)

Question 1

definition of community

Answer 1

• groups of species that occupy the same geographic area

Question 2

The general steps of species establishment

Answer 2

1. species disperse to new areas
2. local environment places selective pressure on species
3. those with traits that allow survival and reproduction establish
4. others die off
5. newly-established species affect local ecology

Question 3

abiotic/biotic limitations

Answer 3

biotic: predation, herbivory, mates, competition, resources (limited), disease
abiotic: temperature, water, salinity, sunlight, rocks and soil

Question 4

How the assembly of plants influences community structure and zonation

Answer 4

• communities are organized spatially as abiotic factors influence plant variation
• plant variation will dictate animal life & fungi

Question 5

How we generally quantify species diversity (two components) and what “S” is

Answer 5

• richness (S): # of species
• eveness (E): relative abundance of species

Question 6

what disturbance and succession are

Answer 6

disturbance: relatively fast event (evolutionary timescale)
succession: primary and secondary; ex (volcanoes, fires, climate change, new species)

primary: opening of uninhabited, unfertile habitat (1000+ years); no biological legacy
secondary: major disturbance occurs on preexisting soil and some vegetation; biological legacy is there

Question 7

why volcanoes are good for the study of primary succession

Answer 7

• most destructive type of natural disturbance and initiate primary succession
• soils and communities can eventually develop
• extremely little biological legacy, succession starts from a blank slate

Question 8

• General steps of primary succession and the highlighted characteristics of early/late successional species

Answer 8

1. physical amelioration occurs first
2. some locations become more favorable
3. edges and rocks protect pioneers
4. pioneers can increase nutrients, trap seeds, protect new plants

Question 9

“pioneer”

Answer 9

pioneer species establish first