exam 2 lecture 3 Flashcards
What gender does a higher amount of testosterone equate to?
a male presentation
What gender does a lower amount of testosterone equate to?
a female presentation
is gender a spectrum
There is a wide range between hypermale and hyperfemale traits.
The distribution of gender-related characteristics forms a gradient
rather than a strict binary.
Some individuals fall outside traditional male and female
classifications.
Do neighboring embryos contribute to hormonal influence?
Neighboring embryos contribute to hormonal influences in development.
embryos with less testosterone have more or less nuturing behaviors
Embryos with reduced testosterone show more nurturing behaviors
typically seen in females.
testosterone antagonists
Using testosterone antagonists can lower testosterone and alter
sexual characteristics.
testosterone agonists
Using testosterone agonists increases testosterone levels and
enhances male traits.
is testosterone the only factor that influences sexual orientation?
Testosterone plays a crucial role in determining gender, but it is not
the only factor influencing sexual orientation.
testosterone levels in homosexual males and females
Homosexual males tend to have lower testosterone levels, while some homosexual females have higher levels.
What happens to the size of the hypothalamus in homosexual males?
Certain brain structures, such as the hypothalamus, are smaller in
homosexual males compared to heterosexual males.
Why has natural selection not eliminated homosexuality?
Some theories suggest that homosexual individuals may contribute to the survival of their relatives’ offspring. evidence shows this is stronger in animal species than humans
Many species engage in sexual behaviors for bonding reasons and reproductive reasons; which category of animal only does it for reproducive purposes?
Insects, by contrast, typically exhibit sexual behavior only for
reproductive purposes.
differences between bonobos and chimpanzees
Bonobos
Exhibit low levels of aggression.
Resolve disputes through sexual behavior rather than physical conflict.
Their social system prioritizes relationships and cooperation over gene propagation.
Chimpanzees
More aggressive in nature compared to bonobos.
Have a broader range and are more widely distributed.
Their aggression may contribute to their evolutionary success.
in alligators, what determines the sex of offspring?
In species like alligators, nest temperature determines the sex of offspring.
High temperatures may result in the development of females, while low temperatures lead to male development.
Protandrous hermaphrodites
first function as males before becoming females. Some fish species change their functional sex over their lifespan. The availability of females in the population can trigger this transition.
critical periods
Critical periods are specific windows in development when
particular biological or behavioral changes occur. These periods shape the final attributes of an organism.
imprinting
Imprinting occurs when an animal forms an attachment to a specific
stimulus early in life. It requires the stimulus to be of a roughly correct shape and moving at an appropriate speed. Once an animal imprints, it is less likely to imprint on another stimulus later.
how do animals choose mates (scent)?
Animals often choose mates based on early sensory experiences.
A rat pup nursed by a mother with a specific odor (cherry or golden) will later prefer mates with a similar odor.
precocial animals
More developed at birth.
Capable of movement and independence shortly after birth.
ex: Ground-dwelling birds and deer.
altricial animals
Born less developed and dependent on parental care. Typically found in species that have safer nesting areas.
ex: birds that nest on cliffs and trees.
Why are humans different from most altricial species?
Humans are born highly underdeveloped (altricial).
They have a small litter, unlike most altricial species.
Rat pups were tested with two different maternal scents, one from the biological mom and a non-mother.
The rat pup usually selects the nipple closest to the scent of its
biological mother
What does mammalian breast milk contain?
A low concentration of an
opiate precursor. This precursor can be converted into morphine in the infant’s digestive system.
exogenous opiates
Exogenous opiates (those derived from plants) mimic these natural
mechanisms.
sensitive periods
Allow for gradual transitions and impact sensory perception, social bonding, and language acquisition
Can a transgender nurse an infant?
Yes, this demonstrates the flexibility of mammalian biological systems in response to environmental stimuli.
How many sounds can humans initially discriminate?
around 100 different phonemes but overtime lose them if they are not present in their environment
Do genetic predispositions play a role in learning?
Genetic predispositions play a significant role in learning and
cognitive development. These predispositions can impact the way individuals process and respond to environmental stimuli.
During a sensitive period, what happens to visual perception?
Individuals can better discriminate between lines when presented vertically or almost horizontally.
rather than horizontally.
Studies in other species show that they, too, have predispositions to better discriminate between vertical and horizontal lines. In a study involving kittens raised without exposure to straight lines. They struggled to discriminate between lines once adults, highlighting the importance of
early environmental exposure.
developmental homeostasis
Developmental homeostasis is the ability of organisms to compensate for environmental differences, resulting in similar outcomes despite varying conditions. ex: children in Amsterdam during WWII who experienced severe malnutrition had normal cognitive development despite bad conditions. Humans have a genetically programmed ability to maintain relatively normal development.
genetic sensitivity
A particular gene variation can make individuals more
susceptible to environmental factors, such as stress or
deprivation. Those with this gene variation may experience more
negative outcomes in poor environments but thrive in
positive, nurturing environments.
are humans more or less developed than other great apes
Humans are considered underdeveloped at birth compared to other great apes, as they retain a
youthful form into adulthood.
how is playfulness different between humans and great apes?
Humans retain playfulness throughout life, unlike other great apes who outgrow it.
Do all species fully mature?
Some vertebrate species complete their life cycle in an immature
form. They never grow beyond a juvenile state but still reproduce.
ex: Salamanders
Amphibians typically undergo metamorphosis, where larvae
lose their tails upon maturing. Certain salamanders retain larval characteristics throughout
life. Despite looking like larvae, they reproduce as adults. This phenomenon is called paedomorphosis.
why are salamanders immature?
Scientists injected salamanders with growth hormone. The treated salamanders absorbed their tails and matured into
adult forms. This suggests their immature state is due to suppressed growth signals.
paedomorphosis
Retaining juvenile traits into adulthood while remaining
reproductively mature.
neoteny
Slower development, spending extended time in an immature state.
what neotenous traits do humans exhibit
Humans exhibit some neotenous traits, such as prolonged childhood and delayed physical maturity compared to other species.
Did early animals have backbones?
Early animals did not have backbones. The first vertebrates developed notochords, which are flexible rods supporting their bodies.
tunicates
Tunicates (sea squirts) start life as free-swimming larvae with
notochords. Upon maturing, they attach to the ocean floor, absorb their tails, and lose their notochords. Some scientists suggest that vertebrates evolved when certain ancient tunicate-like species retained their larval traits into adulthood.
what is the predictable life cycle species follow?
Growth, reproduction, and reproductive senescence.
do any species not experience reproductive decline?
Some organisms do not experience reproductive decline
ex: Turtles: Older individuals become more fertile with age.
Marine animals: Some continue reproducing indefinitely until external factors end their lives.
what species reproduces before reaching full maturity?
Some species reproduce before reaching full maturity.
Example: A small opossum species reproduces while still appearing juvenile.
praying mantis lifespan
In certain species, males die soon after mating, while females
live much longer. Prairie mantises have a reversed dynamic where females dominate.
what do all behaviors have
physiological roots including homosexuality. Homosexuality arises from all of us being hermaphrodidtic
atlantic leatherback turtles and their nest temperatures
A high nest temperature results in males developing. The temperature is extreme enough to override the genetics
endogenous opiates
(inside the body) opiates in the form of endorphins (play a critical role in regulating dopamine levels which helps with pain)
How many phonomes do most languages have?
40-60
what does it mean if someone has a double recessive risk allele
both genes are the risk gene theyre much more influenced by the environment than others
Very sensitive to their upbringing environment
These individuals are called orchids
what is reproductive senescence?
lose the ability to reproduce
