What is Behavioural Ecology? Flashcards
Adaptation
- The evolutionary process by which organisms fit better into their environments or habitats
- A physical or behavioural trait maintained and evolved by natural selection that enhances the probability of survival and reproduction
ie. bird flight – large chest muscles for wings, hollow lightweight bones, etc.
What traditions does behavioural ecology unite?
Ethology and Evolutionary Biology
What are the three components of natural selection?
Variation, Inheritance, Competition
Isla Daphne and the medium and large ground finches
A long term study by the Grants, who studied on the island for over 50 years.
- 1977: Dry year, seed abundance plummeted and the population crashed. Most of what remained were large hard seeds, which most medium ground finches could not open. Those with larger beaks survived / were selected for, and average beak size went up.
- 1982: New competitor arrives. Large ground finch outcompetes medium ground finch for big seeds, as they were very efficient at ripping them open.
- 2004: Another draught. Populations of both species of finch decreased. Medium ground finches that survived had narrower beaks, as the large ground finch outcompeted them for large seeds.
Evolution
Change in the genetic composition of a population over successive generations. Driven by natural selection. Results in new species.
Natural Selection
A process by which traits become more or less common in a population, because they lead to differential survival and reproduction of individuals possessing them.
Fitness
An organism’s ability to pass on genetics to its offspring. (AKA, a measure of an individual’s reproductive success.)
Character Displacement
Divergence in traits that is caused by competition between species.
Character Release
In the absence of competition, a trait can shift around more and is less constrained.
