lecture 10 Flashcards
hormones
biochemical regulators affecting animal physiology and behavior
secreted by endocrine glands
hormones are constantly secreted into blood and travel to target tissue
2 effects of hormones
some hormones are organizational and some are activation
organizational hormones
they organize neurons typically early on in an organisms life
activational hormones
high levels of hormones can trigger a behavior but the effects can be short
testosterone and the challenge hypothesis
first described in birds, during the mating season season breeders with male to male competition show an increase in T levels compared to non-breeding season where it returns to baseline
testosterone and parental care
high testosterone is not compatible with parental care
high testosterone gets more copulation, but not as involved in parental care of offspring
testosterone and prolactin
males that carry infants have higher levels of prolactin hormone, and high levels reduces aggression because high prolactin equals low testosterone
they are antagonist hormones
glucocorticoids
stress hormones that can have immediate adaptive benefits that increase fitness
affects of glucocorticoids
- increase blood sugar
- promote muscle catabolism
- limit hormones that suppresses appetite
too much can kill
pheromones
substances that are endogenous (produced within the body from exocrine glands) and communicate information between conspecifics often go air born or rest on a substrate. They are usually taken in the olfactory system
Role of exocrine glands
they release pheromones onto the surface of the body or in the urine which can then float through the air or stay on a substrate
VNO (vomeronasal organ)
specific receptor of pheromones which a part of most reptiles, most mammals, and some amphibians
3 types of pheromones
- sexual pheromones
- primer pheromones
- social (signal) pheromones
sexual pheromones
pheromone dealing with sexual attraction and elicits a response
ex: silk moths flutters her wings, pheromone is released into the air, and then a male flies in
primer pheromones
pheromones that influence an animal’s physiology once the pheromone has been received
ex: bruce affect in female mice
social pheromones
pheromones that provide information by a chemical signal which may or may not elicit a behavioral response
Major Histocompatibility Complex (MHC)
most gene dense area of human’s genome, highly polymorphic, highly variable that presents an immune system response
genes involved in the immune system and are most diverse between individuals. these genes then code for proteins that kill invading pathogens.
T-Shirt Test
pheromones act as attractants which is linked to MHC
49 women and 44 men
men wore a clean t-shirt for 2 days and then women smelt them and rated them based on attractiveness. the women picked shirts from males with the most dissimilar MHC complex
