Hormones-Pheromones Flashcards
Hormone Defined
biochemical regulators, affect animal physiology and behavior. Secreted by endocrine glands. Constantly secreted into blood, travels to target tissue
Two Effects of Hormones
Organizational: set up body for task. e.g. organize neurons early in organism’s life
Activation: trigger a behavior
Challenge Hypothesis & Testosterone
seasonal breeders that experience male-male competition have increased testosterone during the mating season. Promotes aggression so they can defend their territory and females
Relationship Between Testosterone & Parental Care
parental care is not compatible with high testosterone
Relationship Between Testosterone & Prolactin
Prolactin reduces aggression, is compatible with parental care
If one is high, the other is low
Stress Hormones-Glucocorticoids
have immediate adaptive benefits that increase fitness (increase blood sugar, promote muscle catabolism, limit hormones that suppress appetite).
support behaviors needed to survive in stressful environments
Pheromone Defined
produced by exocrine glands, communicate information between conspecifics. Airborn or rest on a substrate. Taken in by an animal’s olfactory system.
What is the VNO
vomeronasal organ. detects pheromones
Three Types of Pheromones (type-definition-animal example)
Sexual - indicates sexual attraction, readiness to mate. (e.g. silk moth, F put out pheromones for M, M finds her using pheromone catchers – antennae)
Primer - induces physiological change (e.g. Vandenbergh effect – urine of M mouse makes F mouse sexually mature)
Social (signal) - provides information (e.g. dogs scent mark to mark territory, recognize individuals, and indicate F reproductive state)
Major Histocompatibility Complex (MHC) Defined
a group of genes essential for immune system functions. Highly polymorphic and variable, most diverse between individuals.
T-Shirt Test (Attraction & MHC)
Pheromones as attractants. F smelled M T-shirts, they smelled sexier if the Ms had dissimilar MHC complexes
