Outline Lecture 14 Mating 3
A. To Bond or Not to Bond?
1. Time Budgets
– Somatic effort vs. reproductive effort (which is mating effort + parental investment)
-evolutionary tradeoffs: all organisms have limited time and energy budgets.
Time/effort solving one problem means less time/energy available for other problems
– somatic effort: investment in growth & maintenance. Anything that promotes well
being (job, education)
– reproductive effort: mating effort + parental investment. Things one needs to
reproduce, attract a mate, hold onto a mate, raise kids.
– Mating effort: effort expanded in attracting or retaining mates (weaponry, etc)
– parental investment (P.I.): any investment that increases an offsprings survival (&
reproduction) but decreases the parent's ability to invest in other (including future)
– time÷effort spent on mating effort cannot be spent on parental investment, vise versa
2. Why Form Long-Term Bonds?
-imagine this: you've just met someone who is interested in you (& possibly mated with
Q: should you form a long-term pair with him/her?
-which one provides a higher return:
mating effort (towards others) vs. parental investment
does attempting to remate > attempting to pairbond?
Attempting to pair-bond:
-guaranteeing conception with that person
-future offspring with same partner
-effects of parental investment on children's success
-mutual cooperation & division of labor
Attempting to remate:
-likelihood of remating (including availability of mates and your likelihood of
getting one (how many fish in the sea? What is likelihood of catching one?)
-effect of your reproductive success of mating with an additional person
3. Different Strategies for Different Folks
-focus on long term
-advertise character, partner fidelity
-focus on short term
-spend more time advertising individual quality: attractiveness, physical ability
**strategies that pay off for some may not payoff for others** – Facultative responses: strategies which are contingent on one’s condition/situation
-single mental design, but different behaviours depending on one's condition or
situation (same mentality, but some individuals are better and worse off than
-different individuals face different conditions, so their “best responses” or
“optimal strategies” may differ
-e.g. “if big, be aggressive. If small, be conciliatory
-e.g. “if attractive, pursue ST strategy& be more discriminating. If not, offer LT
strategy and/or be less discriminating
-less restricted attitudes about casual sex
-invest more in pursuing affairs
-invest less in relationships (all else equal. e.g. quality of his partner
-greater preference for symmetry in good looking women
- The “best” mating strategy depends on one’s mate value
- Stressful environments: why wait for a better future if it’s unlikely to come?
-tradeoff of somatic vs. reproductive effort: