EEB 100 Lecture 8.2

Territoriality and communication

Habitat suitability

measured in terms of the reproductive success (or feeding rates, etc.) of individuals

Habitat distribution

The number of individuals of a given species in each of its different habitats.

Territoriality benefits

access to resources, spacing benefits (parasite avoidance), site fidelity benefits (familiarity with resources)

Territoriality costs

defending requires time and energy, risk of injury, predation & risk of losing territory to superior competition

Payoff Asymmetry hypothesis (territory)

Territory holders value territory more than competitors (resident may have greater payoff than newcomer, more familiar with location)

Honest signaling (communication)

Mutual fitness benefit from an evolved exchange of information (honeybee dance)

Deceitful signaling (communication)

Sender uses an evolved signal to manipulate the behavior of the receiver, so only the sender has a fitness benefit

Eavesdropping (communication)

Receiver makes use of incidental cues from sender to gain fitness benefit at the expense of the sender

Preexisting trait hypothesis (evolution of communication)

signals arise from existing traits that already provide informative cues and can be modified into a signal

Preexisting biases hypothesis (evolution of communication)

Signals arise through biases in existing sensory systems that can be exploited by sender signals

Ideal Free Distribution Model

assumes 3 things:

1) individuals are free to move between patches

2) they can tell the quality of a patch

3) they compete for resources, so resources dwindle with higher density