NBB 201 Exam 2

Nature vs Nurture Argument

Asks how much of a person's traits, behaviors, and abilities come from nature (genetics and biology, i.e., inherited characteristics) versus nurture (environment and experience, i.e., upbringing, culture, learning, relationships, and other external influences).

Eugenics

“noble in birth”

positive eugenics

increase the birth rate/population of people who are of “noble birth”

negative eugenics

decrease the birth rate/population of people who are of “noble birth”

Interactants in Developmental Systems

the genome, cell structure (including organelles), intracellular chemicals, extracellular environment, parental reproductive systems, self-stimulation by the organism itself, immediate physical environment, conspecifics and members of other species, climate - food sources - other aspects of physical environment

Positive feedback system

A feedback system in which the response amplifies or reinforces the original stimulus, pushing the variable further from its starting point. It drives a process to completion rather than maintaining stability.

Negative feedback system

A feedback system in which the response opposes or reduces the original stimulus, bringing the variable back toward its set point. It maintains homeostasis and is the most common type of hormone regulation.

Intacrine mediation

cellular signaling that happens within a cell

Autocrine mediation

when a chemical signal is produced it leaves the cell but then acts on itself on the same cell

Paracrine mediation

chemical signaling that happens between two cells that are close together in space

Endocrine signaling

chemical signaling that happens between two cells that are far away in space through being released into the bloodstream

Neurotransmitters

secreted by neurons to other neurons (e.g. dopamine, epinephrine) *at least 60 in the brain!

Neurohormones

secreted by neurons into bloodstream (e.g. releasing/inhibiting hormones)

hormones

chemical messengers that travel through the bloodstream to transmit info from one part of body to another, secreted by endocrine glands into bloodstream (e.g. most of the hormones we cover in class)

endocrine system

a network of hormones, receptors, carrier molecules, and signaling pathways that lets cells and organs communicate over a distance, typically via the bloodstream, to regulate metabolism, growth and development, reproduction, and responses to internal and external stimuli.

Neural communication vs Hormonal communication

Space(close/far), Time (quick/slow)

Dopamine

a neurotransmitter associated with reward

Serotonin

a neurotransmitter associated with mood

Norepinephrine

a neurotransmitter associated with the stress response

Hypothalamus

Coordinates between brain and body via the endocrine system, essential for homeostasis and behavior, common to all vertebrates

Hypothalamic neurohormones

Corticotropin-releasing hormone (CRH), gonadotropin-releasing hormone (GnRH), Thryrotropin-releasing hormone (TRH), growth hormone-releasing hormone (GHRH), somatostatin, dopamine

Posterior pituitary

contains neurons that produce and secrete peptide hormones (doesn’t produce any hormones), neurons run from hypothalamus to PP, at PP neurons release hormones into bloodstream
-vasopression (AVP), anti-diuretic hormone (ADH), oxytocin (OT)

Anterior pituitary

Neurons in hypothalamus produce releasing or inhibiting hormones, hypothalamus uses exclusive bloodstream to send hormones to AP, can stimulate/inhibit release of AP’s own hormones
-Adrenocorticotropic hormone (ACTH), gonadotropins (LH, FSH), thydroid-stimulating hormone (TSH), growth hormone (GH), prolactin

Endocrinology

All study of hormones, their production, their target cells, and their effects

Behavioral Endocrinology

A subset of endocrinology studying the interactions between hormones and behavior

Factors that effect how hormones work

Variation in hormone levels, hormone receptors, in the sensitivity to hormones

Up-regulation

when receptors are increased

Down-regulation

when receptors are decreased

Vertebrate hormones

steroid hormones, peptide hormones, amine hormones

Steroid hormones

small hormones comprised of a cholestrol subunit, not soluble in blood, not stored, slow acting, long biological half life (e.g. glucocorticoids, androgens, estrogens, progestagens)

Steroid Hormone action

Steroid hormones diffuse into the target cell and bind an intracellular receptor. The hormone-receptor complex enters the nucleus and changes gene expression, which alters protein synthesis over hours to days.

Peptide hormones

Large hormones comprised of amino acids, soluble in blood (no carrier protein needed), stored in endocrine cells, fast acting, short biological half-life (e.g. LH, FSH, ACTH, insulin, glucagon)

Peptide hormone action

Peptide hormones bind a receptor on the cell membrane and can't enter the cell. The hormone-receptor complex stays in the membrane and triggers signal transduction, which activates second messengers that change cellular activity.

Amine hormones

hormone derived from a single amino acid, usually tyrosine (or tryptophan for melatonin). Amine hormones behave differently depending on their type: some act like peptide hormones and some like steroid hormones.

Parasympathetic NS

Rest and digest: cholinergic neurons → release acetylcholine

Sympathetic NS

Fight, Flight, or freeze: adrenergic neurons →release epinephrine/norepinephrine

Follicle-stimulating hormone (FSH)

Anterior pituitary gonadotropin that promotes follicle development in females and sperm in males.

Luteinizing Hormone (LH)

Anterior pituitary gonadotropin that triggers ovulation in females and stimulates testosterone production in males.

Gonadotropin-releasing hormone (GnRH)

Hypothalamic decapeptide that triggers anterior pituitary release of LH and FSH (HPG axis).

Hypothalamus

-Gonadotropin-releasing hormone (GnRH) → Bind in anterior pituitary to stimulate

hormones (FSH, LH)

Anterior Pituitary

Secretes FSH and LH that bind to androgen receptors (ARs) in testes

Meta-analysis

Statistical method that pools results from multiple independent studies to give one more precise overall effect estimate.

“operator syndrome”

The confluence of overlapping and interrelated factors creates a viscious cycle resulting a SOF operator with compromised functioning and impaired ability to transition to civilian life.

aggression

overt behavior with the intention of inflicting damage on another individual

Challenge Hypothesis 1.0

1990 idea that androgen levels peak during periods of intense competition for territory and mates, and decrease when males engage in parental care (male-male interactions emphasized)

U.S. Govt Sex Definition

Female: person belonging at conception to the sex that produces the large reproductive cell
Male: person belonging at conception to the sex that produces the small reproductive cell

Isogamy (ancestral form)

two equal-sized gametes

Anisogamy/Oogamy

Male: small gamete, Female: large gamete

chromosomal sex

An individual's sex as determined at conception by which sex chromosomes (X and Y) they inherit. These make up one of the 23 pairs of chromosomes in humans. The Y chromosome's genetic makeup is largely responsible for the downstream development of male-sexed traits.

chromosomal mosaicism

Presence of two or more cell lines with different chromosome complements in one individual, all derived from a single zygote. Caused by post-zygotic errors (e.g., mitotic nondisjunction), so only some cells are affected. Earlier error = more cells affected.

gonadal sex

Sex defined by the type of gonads present: testes or ovaries. It is determined by the developmental pathway of the bipotential gonad, which in most cases is driven by the presence (SRY, leading to testes) or absence of SRY-dependent signaling (leading to ovaries).

Organizational Effects

long-lasting hormone effects take place during critical periods in development

Activational Effect

short-lasting hormone effects “activate” the circuits organized by hormones in development

anatomical sex

Sex defined by the physical sex characteristics of the body: internal reproductive structures (e.g., uterus, vas deferens), external genitalia, and secondary sex characteristics. It develops downstream of gonadal sex, shaped mainly by hormones the gonads produce (testosterone, DHT, anti-Müllerian hormone).

Factors that modulate the onset of puberty in mammals

Circadian cycle, season, stress, metabolic factors, pheromones,feedback from current state

plumage polymorphism

Two or more discrete, genetically determined plumage morphs coexisting in one interbreeding bird population. - 4 different “breeding types”, 2 different “pair types”

disassortative mating

females seek different SEX and different MORPH

Estrogen Receptor 1 (ESR1)

-widely expressed in brain, related to aggression, and in WS

-ESR1 expression in WS is what directly leads to aggro, if you bring to TS ESR1 levels, no aggro

Vasoactive intestinal peptide (VIP)

important neuromodulator in both aggression and parenting behavior, more expressed in WS

-stimulates release for prolactin (more provisioning behavior)

Why “4 sexes” in white-throated sparrows

-Substantial genetic variation by chromosomal sex (bird vers of XX + XY)
-Substantial genetic variation by morph (2/2 or 2/2m)

Intrasexual selection

Compete with same sex to choose mate (associated with physical fights and displays aimed at same sex)

Intersexual selection

Compete to be chosen by the other sex (associated with courtship displays and ornamentations, extravagant traits)

Sexual Selection vs Natural Selection

Struggle for mates + differential reproduction vs struggle for survival + differential survival

Essential elements for sexual reproduction

Finding/accessing a mate, succesful fertilization, producing viable & fertile offspring

biological sex

2 different sized gametes

sexual differentiation

how do you go from 1 cell embryo to multicellular organism (SRY, hormones, puberty)

sex-typed behaviors

from genes to hormones & receptors to behaviors to life history strategies

sexual behavior

from behavior to fertilization, any behavior that may contribute to reproductive sex, or mechanistically: any genital contact or manipulation

Institut fur Sexualwissenschaft

-First sexology institute of the world

-contained unique library on gender, same sex love, and eroticism

-offered services to public: treatments for alcoholism, gynecological exams, sex counseling

-nazis came in and burned everything down

Paragraph 175

outlawed sex between men in Germany from 1871 to 1995 (following WW2, west germany kepts these laws east germany reverted to its milder version)

Gertrude van Wagnen

1893-1978 prof at Yale who was a pioneer in reproductive endocrinology, discovered contraceptions through study of monkeys

Dr. Joycelyn Elders

Director of Arkansas Dept of Health, first black surgeon general of US, advocated for access to contraception to tackle health disparities+ sexual education in schools → later forced to resign b/c supported abortion + advocating for sexual education (ex. masturbation)

Stages of sexual behavior

Before: Motivation, dopamine, sex hormones
During: Consummation (orgasm), dopamine, endogenous opioids
After: Satiety, seratonin, oxytocin, endocannabinoids

Components of rat maternal behavior

-Nursing, licking and grooming, nest building, pup retrieval

-male + nulliparous female rats avoid & even attack pups

-post-partum fem rats are immediately maternal post-partum

Oxytocin synthesis

oxytocin is synthesized in the PVN/SON part of hypothalamus → released from posterior pituitary gland into general circulation ( causes uterine + milk duct contractions OR → released into brain

Mesolimbic DA System

Dopamine neurons concentrated in midbrain (VTA) → sends axons + releases dopamine into NA (mesolimbic pathway)

Medial Preoptic Area (MPOA)

MPOA activates approach (mesolimbic DA) system and inhibits avoidance (amygdala) system, contains lots of steroid receptors + hormones

Romantic love

A strong emotional and physical attachment that combines passion, intimacy, and an idealization of another person

Dopamine

A neurotransmitter involved in reward, motivation, movement, and learning. Is released in anticipation of a previously-rewarded action and upon receiving reward

agonist

A substance that binds to a receptor and activates it, mimicking the body’s natural messenger (e.g., pramipexole activating dopamine receptors).

antagonist

A substance that binds to a receptor but does not activate it, blocking the natural messenger from producing its effect (e.g., haloperidol blocking dopamine receptors).

oxytocin

A hormone and neurotransmitter made in the hypothalamus and released by the posterior pituitary. It triggers uterine contractions during labor and milk ejection during breastfeeding, and it promotes social bonding and trust. (very connected to dopamine!)

Androgens

Steroid hormones that drive the development and maintenance of male characteristics, such as muscle mass, body hair, and sperm production (e.g., testosterone).

Estrogens

Steroid hormones that drive the development and maintenance of female characteristics, such as breast development and regulation of the menstrual cycle (e.g., estradiol)

Social bonds w/ potential function & tie to reproduction

male bonds w/ lactating females (infant protection?), male-female relationships, male-infant relationships (both mating investment..?)

Social bonds w/ direct functional tie to reproduction

parent-infant, pair-bond (permanent), consortship (temporary)

principle of inherited association

A behavior that was once useful in a certain situation becomes linked to the emotion felt in that situation, and that link is inherited, so the behavior still appears whenever the emotion is felt, even when it no longer serves a purpose (e.g., bird singing to expression when they feel happy even though singing is also used to attract mates)

Play behavior

play is repeated, seemingly non-functional behavior differing from more adaptive versions structurally, contextually, or developmentally, and initiated when the animal is in a relaxed, unstimulating, or low stress setting

Kinds of play

locomotor/rotational play, object/predatory play, social play

Affiliative behaviors

sexual behavior, grooming behavior, play behavior

Common function of affiliative behaviors

strengthening social bonds, neural & motor development, stress reduction

Common affiliative behavior mechanisms

DA & OT reward circuits, endogenous opioids, activating nervous system

Endogenous opioids

Natural chemicals made by the body that bind to opioid receptors to reduce pain, relieve stress, and produce feelings of pleasure or reward (e.g., endorphins, enkephalins, and dynorphins).

Optimized “Warfighter Readiness”

A military goal of maximizing soldiers’ physical and mental performance and resilience for combat, while preventing breakdowns like injury or overtraining.

overtraining syndrome

Training too hard without enough recovery leads to body going into extended stress response, long-term fatigue, declingin performance ALSO often accompanied by hormonal disruptions (e.g., altered cortisol and testosterone levels), mood changes (irritability, depression), sleep problems, frequent illness or injury.

nucleus acumbens

A brain region in the ventral striatum that’s a key part of the mesolimbic reward pathway. It receives dopamine from the VTA and processes reward, motivation, and pleasure, driving behaviors like eating, social bonding, and addiction.

Challenge Hypothesis 2.0

Variations in androgens is mainly a function with reproductively active females

→males with parental care should maintain high androgen (but low T) levels as long as rep females available, might mount short-term responses to male-challenges

→males with no parental care should have high androgen levels too as long as rep females available, might mount short-term responses to male-challenges

Pete Hegseth

US Secretary of War that is pushing for t-testing in soldiers to address operator syndrome

Types of Aggressive Behavior

Offensive aggression, maternal aggression, defensive aggression

Challenge Hypothesis + Humans

Strongest evidence is about parental care, Data on T and competition is highly variable