Sexual friendships
Sexually transmitted diseases
Sexual orientation
Sexual plasticity
Sexual pleasure Sexual arousal
Siberian/Arctic peoples
Siblicide
Sikes, S. K.
Single parenting in pair-bonding species (heterosexual) mammals waterfowl shore birds perching birds other birds
Situational homosexuality
Skewed sex ratios
Smuts, Barbara
Social, spatial responses (toward or by homosexual/transgendered animals)
interference, hostility toward mammals birds
nonchalance, curiosity toward
offensive attacks by mammals birds
partner defense by mammals birds
rank/status of
segregation/separation by
territory defense by mammals birds
Sorum, Arve
Soule, Michael E.
Sources of offspring (homosexual parenting)
adoption (coparenting by nonbreeders)
coparenting by breeder and nonbreeder
egg/nest-stealing
foster-parenting in captivity
joint parenting by breeders
mating within bisexual trios/ quartets
nonmonogamous mating
parasitism (egg “donation” by other birds)
Sperm competition theory
Sperm storage
Standing Bear, Luther
Stephenson, Robert
Step-parenting
Steward, Daniel-Harry
Stress of breeding
Supernormal clutches waterfowl shore birds perching birds other birds
Supra-annual breeding cycles
Taboos
Tafoya, Terry
Tennent, W.J.
Terminology for homosexuality/ transgender
use of
use of