43 terms


chapter 8 bold terms
asexual reproduction
reproduction without the sexual union of gametes
a group of asexual individuals, all descended from the same parent and bearing the same genotype
in plants, the occurrence of male and female sexual organs on different individuals
having two sets of chromosomes
extra-pair copulation (EPC)
copulation between a paired female and a male that is not her mate
in sexual reproduction the union of male and female gametes to form a zygote
Frequency dependent selection
differential survival or reproduction that depends on the frequency of a phenotype in a population
a haploid cell that fuses with another of the opposite sex during fertilization to form a zygote
the primary sexual organ in which male or female gametes are produced
handicap principle
the idea that elaborate, sexually selected displays and adornments act as handicaps that demonstrate the generally high fitness of the bearer
a sex determination mechanism in which females develop from fertilized eggs and are diploid, and male develop from unfertilized eggs and are haploid
having a single set of chromosomes
an individual that has both male and female sexual functions
mating between closely related individuals
local mate competition
competition among males for mates that occurs at or near their place of birth, and hence potentially involves competition between close relatives
mate guarding
close association of males with their female mates to prevent their mating with other males
mating system
the pattern of mating between males and females in a population, including the number of simultaneous or seq. mates, the permanence of pair bonds and the degree of inbreeding
a series of two divisions by cells destined to produce gametes, involving pairing and segregation of homologous chromosomes and a reduction of chromosome number from diploid to haploid
in plants the occurrence of male and female sexual organs in different flowers on the same individual
a mating system in which each individual mates with only one individual of the opposite sex, generally involving a strong and lasting pair bond
mating between unrelated individuals in hermaphrodites, fertilization that takes place between games from different individuals
parasite mediated sexual reproduction
the idea that females choose male mates on the basis of secondary sexual characteristics that indicate their ability to resist parasite infection
reproduction without fertilization by male gametes, usually involving the formation of diploid eggs whose development is initiated spontaneously
a parasite especially a microorganism, that causes disease in its host
perfect flower
a flower having both male and female sexual organs
a mating system in which a female pairs with more than one male at the same time
a mating system in which a male pairs with more than one female or a female pairs with more than one male at the same time
a mating system in which a male pairs with more than one female at the same time
polygyny threshold
the degree of variation among territories at which the reproductive success of a female that pairs with a polygynous male holding a high quality territory is likely to equal that of a female that pairs with a monogamous male holding a lower territory quality
mating with many individuals of the opposite sex, generally without the formation of strong or lasting pair bonds
Red Queen hypothesis
the idea that evolutionary change in a pop. biological environment, especially in its predators and pathogens, applies continual selection pressure on that population
Runaway sexual selection
sexual selection by female choice that results in elaborate and costly secondary sexual characteristics in males
secondary sexual characteristics
traits other than the sexual organs themselves that distinguish males and females
self-fertilization: a form of sexual reproduction in which a hermaphroditic individual forms both male and female gametes and fertilizes itself
sex ratio
the ratio of the number of males and females within the progeny of an individual or within a population
sexual dimorphism
a difference in the phenotypes of males and females of the same species
sexual reproduction
reproduction by means of the union of two gametes to form a zygote
sexual selection
selection by one sex for specific characteristics in individuals of the opposite sex, usually exercised through mate choice
simultaneous hermaphrodite
an individual that both male and female sexual functions at the same time
sequential hermaphrodite
an individual that changes its sex during its lifetime
two-fold cost of meiosis
the 50% fitness cost of sexual reproduction that results in parents contributing only one-half of the genetic material of each of its offspring
vegetative reproduction
an asexual reproductive process by which shoots that sprout from the roots, rhizomes, or leaves of a plant give rise to separate individuals with genotypes identical to that of the parent plant
a diploid cell formed by the union of male and female gametes during fertilization