Reproductive Strategies

Asexual Reproduction Def: Repro not involving genetic exchange between organisms No gametes involved No genetic variety between generations Examples: budding, binary fission, fragmentation

Asexual Reproduction Advantages Disadvantages No need to find a mate (good for solitary animals) Can make many babies fast (opportunistic) Disadvantages No variety, not very adaptable

Sexual Reproduction Def: involves fusion of gametes to form offspring

Hermaphrodites Def: individuals can produce both eggs and sperm Advantages Each individual encountered is a potential mate Twice as much reproductive potential Disadvantage Cost lots of energy to produce both eggs and sperm

Sequential Hermaphrodites Reverses sex during lifetime Ex. Whiptail lizards Wrasse

Mechanisms of Reproduction External fertilization: takes place in the environment Environment must prevent gametes drying up and overheating WATER Timing must be perfect Behaviorally or environmentally cued Eggs and zygotes are not cared for (and good food) Produce MANY

Mechanisms of Reproduction Internal Fertilization: sperm deposited in or near female reproductive tract Often produce fewer zygotes Protected and cared for

Amniotic eggs Look up: what animals have them (3 animal classes)? How are they an adaptation for life on land? Make a labeled diagram, and include the purpose of each structure (p819)