Life History

Question 1

What is the principle of allocation?

Answer 1

If organisms use energy for one function such as growth, then the amount of energy available for other functions is reduced (like reproduction or defense)

Question 2

Describe semelparity and iteroparity.

Answer 2

Semelparity is when an organism invests all of its energy into growth and storage then this is followed by one massive suicidal act of reproduction (ex: salmon, cicadas)

Iteroparity is when an organism produces fewer offspring but has repeated reproduction throughout life (ex: most trees, animals)

Question 3

Provide one example of an ecological trade-off.

Answer 3

If an organism produces larger eggs, but a fewer number of them.

Question 4

List the 6 seed dispersal strategies.

Answer 4

Unassisted: no specialized structures 
Adhesion: hooks, spines, or barbs
Wind: wings, hair 
Ant: oil surface coating
Vertebrate: fleshy coating 
Scatterhoarded: gathered (ex: acorns)

Question 5

What is the relationship between mortality and age of reproduction?

Answer 5

Species with high mortality reproduce at a younger age

Question 6

What is the difference between r-selected and K-selected species?

Answer 6

r-selected species have high rates of intrinsic increase, unstable environments, tend to be smaller with a lower maturation age, and have numerous individual rapidly produced.

K-selected species have high competitive ability, less predators, tend to larger in size, and have less offspring.

Question 7

What are the environmental extremes that plants thrive in? Which don’t they thrive in?

Answer 7

Thrive in: low disturbance, low stress; low disturbance, high stress; high disturbance, low stress.

Do not thrive in high disturbance, high stress environments.