Mating, Sequence of Filters, Male Competition, and Female Choice

Reproduction Disadvantages:

Cost of meiosis (transmit only half of genes), must find mate, predation risk, and primary and secondary sexual characteristics.

Reproduction Advantages:

Muller’s ratchet (accumulation of deleterious mutation in asexuals), Red Queen hypothesis (coevolving parasites/pathogens), and genetic novelty and rapid adaptation.Mo

Types of mating systems:

Monogamy, Polygyny, Polyandry, Polygynandry, and Promiscuity.

Sequence of Filters:

Encounter → Species Recognition → Courtship → Acceptance or Rejection → Copulation → Sperm Storage → Oviposition

Encounter (Who Meets Who):

Habitat structure, population density, resource distribution, temporal synchrony, and mobility and signaling range.

Encounter (Leks):

Communal area where male animals gather during mating season to perform competitive displays to attract females.

Encounter (Long Range Detection):

Plumose antennae for long-distance detection of mates.

Species Recognition (Finding the Right Mate):

Pheromonal attraction, acoustic signaling, visual display and motion, and resource-based mate location.

Courtship (Nuptial Gifts):

May signal mating effort, paternal investment, sensory distraction, and signal of male condition.

Courtship (Communicating Information):

Signal species identity, advertise condition or resources, reduce female aggression or resistance, coordinate timing of mating, and stimulate acceptance.

Acceptance or Rejection (Female Choice):

Females may choose based on signal quality or intensity, male persistence or performance, resource possession, nuptial gifts, and compatibility or pervious mating status.

Acceptance or Rejection (Exaggerated Male Traits):

Females prefer males with longest eye spans, drives runaway sexual selection, genes for the exaggerated trait and genes for the female preference co-evolve.

Acceptance or Rejection (Male-Male Competition):

Direct contests, territoriality, scramble competition (indirect, race to find mate), interference with signals, and guarding of females or oviposition sites.

Acceptance or Rejection (Direct Contest):

Male rhinoceros beetles use their large horns to push, lift, and flip opponents in trials of strength and dominance.

Copulation (The Process of Mating):

Coupling (physical association), Insemination (sperm transfer), and Fertilization (subsequent union of sperm and egg).

Copulation (Copulatory Courtship):

Courtship often continues during copulation, encourage continued female cooperation, increase transfer time, stimulate oviposition or storage, reduce immediate remating, and bias paternity in favor of the current male.

Sperm Storage (Process of Fertilization):

Sperm is frequently stored and used later for fertilization, storage determines which ejaculates are available, how long sperm persists, and whether further mating occurs (generally a queen has one mating flight then uses sperm for rest of life cycle (3-5 years).

Sperm Storage (Sperm Competition):

Competition between ejaculates from different males for fertilization, numerical advantage, displacement of rival sperm, guarding against remating, and manipulating female remating or oviposition.

Sperm Storage (Damselfly Sperm Removal):

Some damselfly males can remove stored sperm from previous males before transferring their own ejaculate.

Sperm Storage (Cryptic Female Choice):

Female bias in paternity after mating has occurred, permitting or terminating copulation, transporting or discarding sperm, differential sperm storage, differential remating, and timing oviposition.

Oviposition (Laying Eggs):

Females decide when, where, and sometimes whether to lat eggs after mating.

Oviposition (Site Selection):

Chosen based on host availability, pathogen exposure, microclimate, predation risk, and competition.