Life History Patterns + Niches Flashcards
What is parental care?
Any behaviour that leads to an increase in the fitness of the offspring
What is the difference between altrical and precocial parental strategies?
Altrical: babies are born helpless and require heavy investment
precocial: light investment, babies have some partial development
What is the semelparous reproductive strategy?
All energy is invested into one big reproductive output in a lifetime
What is the iteroparous reproductive strategy?
Fewer young are produced at one time, but occurs many times throughout life
What is fecundity?
The potential ability of an organism to produce offspring
How do clutch/litter sizes change with an increase in latitude? Why?
Larger clutches/litters as latitude increases. It is the largest number of offspring the parents can feed. Lower predation and an increase in food resources during the summer as latitude increases. The eggs also get smaller as clutch size increases
How does the size of plant seeds relate to number of seeds, growth form, and dispersal mechanism?
Size decreases as the number of seeds produced increases. Climbing plants tend to have larger seeds, grasses have smaller seeds. Bigger seeds are more likely to be eaten by animals and carried somewhere else, and smaller seeds are more likely to be wind dispersed
When would it be beneficial to reproduce early? When would it be beneficial to delay reproduction? What are the downsides?
- Animals with high mortality rates
- More energy can be put into growth, maintenance, and activity and live longer
- Can die before reproducing, have to trade off survival with reproduction
What are characteristics of “r” species?
Reproduce early at high rates with high output. Shorter lived, rapid population growth, low parental care, high dispersal of offspring, environment highly variable
What are characteristics of “K” species?
Reproduce later at lower rates and lower output. Live longer, population grows slower, higher parental care, low dispersal of offspring, stable environment
What are the 3 life history strategies for plants according to Grime’s CSR model?
Competitive, ruderal, stress-tolerant
What kinds of environment does each strategy do best in?
a) competitive
b) ruderal
c) stress-tolerant
a) low disturbance, low stress habitats
b) high disturbance habitats
c) high stress habitats
What are the characteristics of plants that follow the competitive strategy?
Grow well, but have to compete for resources. Dominate in low stress, low disturbance habitats
What are the characteristics of plants that follow the ruderal strategy?
Grow rapidly, produce lots of seeds very quickly. Thrive in highly disturbed environments
What are the characteristics of plants that follow the stress-tolerant strategy?
Grow slowly, conserve resources. Deals well with high-stress environments
