animal behavior.txt

finding mate consumes time and energy and cost of meiosis is that recombination breaks up favorable gene complexes.

• prevents muller ratchet
• deleterious mutation accumulate in asexual lineages not sexual
• providing long term benefits
• creation of novel gene combination
• red queen hypothesis : must constantly create new gene arrangement to combat pathogen evolution
• providing short term benefits

• genetic ( either chromosomal or genic)
• environmental
• social

• haplodiploid males develop from unfertilized egg
• diploid females develop from fertilized eggs

• it depends on the mating system
• many fish can undergo sex reversal
• dominant female in sea bass changes into male when territorial male disappears.

starting life as female and then changing to male

where male function precedes female function

• parental strategies should evolve towars equal investment in offspring of the two sexes.
• if sex ratio falls below 50% increased production of rare sex is favored

• maternal condition influences offspring investment ( trivers willard effect)
• local mate competition
• local resource competition
• local resource enhancement

• population sex ratio is 1:1, individual sex allocation depends on condition
• if moms in good condition transfer competitive ability to sons more than daughter.
• dominant individual sir more offspring
• they produce more sons then daughters
• female in poor condition should produce more daughters