Chapter 5: Life History- Growth and Development
R.C. Lewontin found that human "races" have no taxonomic significance. He demonstrated this:
through research indicating that most genetic variation is found across human populations
Hypoxia has been shown to be an agent of natural selection in that Tibetan women:
with alleles for high oxygen saturation in their hemoglobin had more surviving children
Franz Boas:
showed that US born children had different head shapes than their immigrant parents
The postnatal stage includes:
the growth of deciduous teeth, motor skills, and cognitive abilities
The growth and development of _____ are more sensitive to environmental impacts than the growth and development of _____
males, females
Genetic adaptation
occurs at the population level via natural selection
Frank Livingstone, a noted physical anthropologist, is famous for having said about human diversity in appearance, "There are no _____; there are only _____"
races, clines
For women with very low body weight, high amounts of exercise can result in:
reduced ability to conceive relative to women who do not exercise
During the adult stage, growth and development is mostly related to the:
replacement of cells and of tissues
Which is a major contributor to the success of our species?
human adaptability
When we look at personal genomics, it becomes ______ to place individuals into categories of biological race
impossible
Cultural adaptation:
involves using material culture to make living possible in certain settings
Melanin
is advantageous because it provides protection from solar radiation
Rickets is the result of:
lack of Vitamin D
Which of the following statements about growth rates among Brazilian children and US children are accurate? (5.11)
-Among US children at the 50th percentile of growth American boys grow for a longer period of time than girls -Brazilian boys and girls grow at a slower rate than the slowest growing 5% of US children -The difference in environment between Brazil and the US explains why children there grow at such different rates -Males' growth tend to be more strongly affected by the environment than females
Which statements about your skeleton is true?
-Athletes tend to have thicker skeletons than non-athletes -Once your skeleton has finished growing, it will not change unless you happen to break a bone -Your skeleton adapts to your workload by increasing or decreasing its thickness
Which of the following describe how the work of Franz Boas challenged the concept of race?
-By studying traits in immigrants, Boas showed that racial types were unstable -By studying traits in both parents and their children, Boas showed that the phenotypic characteristics associated with race can change
Which are potential costs of physical activity?
-Can interrupt reproductive cycle -Can reduce ability to conceive
Which are true about human reaction to heat stress?
-Humans depends on sweat to regulate their temperature more than other primates do -Humans sweat in order to lower their body temperature -Vasodilation occurs when it is hot
Which statements about growth and development are accurate?
-Humans grow at a constant, steady rate during their postnatal stage up to adulthood -During the prenatal stage of life we start as a single cell, undergo mitosis repeatedly, and begin to differentiate these duplicated cells from one another -Among humans grandparents tend to play important roles in the care of young -Dietary or disease stress while your mother is pregnant can predispose you to disease as an adult
Which statements about human life history are accurate?
-In terms of life history, one's environment includes much more than simply climate -Humans have a period of slowed growth called "childhood" that isn't found among many other mammals -Human growth curves are genetically determined, but their timing, speed, and velocity can be changed by the environment -Stressors during critical periods of growth and development can change adult outcomes
Which are ways that human life histories differ from those of other primates?
-marriage between mates -socially important grandmothering role -intensely demanding infant period -long periods of survival after menopause
Traits that R.C. Lewontin found there is more variation within population than between populations
-red blood fell enzyme variants -serum proteins -cranial morphology -blood groups
Put the human life history stages in chronological order of growth and development:
1) The Prenatal Stage 2) The Postnatal Stage 3) The Adult Stage
During the prenatal stage, the growth and the development of the fetus are most dynamic in the ____ trimester
1st
Match each life history event with approx. age at which is occurs in humans:
2-3 years: first set of teeth is present 6 years: brain growth is completed 12 years: puberty begins 15-16 years: sexual maturity is reached 24-25 years: epiphyses fuses to diaphyses
You visit your uncle, a dentist, over winter break. He hands you this x-ray and instructs you to estimate the age of this child, given the eruption time of the permanent molars (6 years old for the first molar, 12 years old for the second, and 18 years old for the third). You reply that the child is between
6 and 12 years old
Cline
A gradual change in some phenotypic characteristic from one population to the next
One of your classmates moved to the US from Somalia as a kid in the late 1990's. After seeing a picture of his family, you notice that he and his sister must have been undernourished for several years. You arrive at this conclusion because your classmate:
And his sister are both much shorter than their parents
Loring Brace argued that the race concept:
Can be traced to the Renaissance, when seafaring travelers observed differences between people from distant lands
A gradual change in phenotype over a geographical area is called a
Cline
Variation in skin color is an example of a:
Cline
High levels of melanin are adaptive at low latitudes because it allows the body to _____ folate. --conserve or produce?
Conserve
One of your classmates asks you for your notes from physical anthropology class. She says she was absent because her mother broke her hip and needed help around the house. This is not the first time the student has been absent for this reason. What would you ask her in an attempt to figure out if her mother is predisposed to osteoporosis? A) Has your mother already gone through menopause? B) Is your mother a heavy smoker? C) Does your mother take a calcium supplement? D) All of the above are correct
D) All of the above
In high school, your parents insisted that you were an adolescent and therefore incapable of living an adult life. You argued, on the other hand, that although you're not 18 yet: A) The onset of puberty had already signaled your adult reproductive capabilities B) Your brain was already full size C) Your complete permanent dentition meant you could eat all adult food D) All of the above are correct
D) All of the above are correct
Children living at high altitudes develop a larger chest cavity by adulthood than children living at lower altitudes. This is an example of:
Developmental adaptations that occur at the level of the individual during critical life stages
Multiple biological traits:
Do not lead to clear-cut racial classifications
Natural selection favored alleles for light skin in:
Eurpe
True or False: Functional adaptations can never be replaced by equivalent genetic adaptations
False
True or False: There are three human races- caucasoid, negroid and monogloid
False, there is only one human race
How many calories per day are consumed in most human populations across the world?
Far less than 2,000
Who was the first scientist to challenge race?
Franz Boas
When epiphyses fuse to the diaphyses:
Full aduly height is attained
Which can be considered a functional adaptation?
Greater diameter of arteries and veins and greater relative blood flow to body tissues, greater lung volume, more efficient use of oxygen, larger chest size in some populations (reflecting greater lung volume)
Which includes a genetic adaptation?
High melanin production-dark skin (they are born with this adaptation)
A major criticism that can be leveled against Johann Bluemenbach's racial typology is that:
His 5 types did not take into account thousands of years of human evolution
Functional Adaptation
Includes both developmental adaptation and acclimization
Allen's rule indicates that humans will have:
Longer limbs in hot environments and shorter limbs in cold environments
What is the adaptive reason for low levels of melanin at higher latitudes?
Lower levels of melanin lead to higher vitamin D absorption at higher latitudes
Sexual maturation or puberty is marked by:
Menarche in girls
The medullary cavities of bone exist in the:
NOT GROWTH PLATES
According to Bergmann's and Allen's rules, all of the following are true except
NOT IGBO NIGERIA NARROW BODIES
In the 1700's, who developed a scientific classification of race?
NOT LEWONTIN
David Barker's research on poor early health led to the hypothesis that:
NOT LOW BIRTH CORR HEART
Acclimatization:
NOT POP LEVEL NAT SELEC
A cline:
NOT VAR DISCRETE CAT OR EARLY REN
Developmental (or ontogenetic) adaptation:
Occurs at the individual level during childhood
There is an old adage that a "fat baby is a healthy baby". A critique of this might be that:
Overnutrition is linked to an increase in diabetes, cholesterol, and blood pressure
Hypoxia occurs when less than the usual amount of ______ is in the body
Oxygen
Although early scientists determined race based on _____ variation, we now know that race can only be determined using information about _____ variation
Phenotypic, Genotypic
The period of time from about 20 years old to the end of the reproductive years is called
Prime
Wolff's Law:
Says that bone mass is taken away where it is needed and produced where it is not needed
In a child, are the epiphyses and diaphyses separated or fused?
Separated by a growth plate
What kind of bodies are found in cold climates?
Short, wide (at higher latitudes)
What kind of bodies are found in hot climates?
Tall, narrow (at lower latitudes)
Menopause
The cessation of the menstrual cycle, signifying the end of a female's ability to bear children
Prenatal Stage
The first stage of life, beginning with the zygote in utero, terminating with birth (involves multiple mitotic events and the differentiation of the body into the appropriate segments and regions
What phenomenon happens in humans but not other apes/primates?
The growth spurt occurring at the onset of puberty
Osteoporosis
The loss of bone mass often due to age, causing the bones to become porous, brittle, and easily fractured
Homeostasis
The maintenance of the internal environment of an organism within an acceptable range
Postnatal Stage
The second stage of life, beginning with birth, terminating with the shift to the adult stage (involves substantial increase in height, weight, and brain growth and development)
Senescence
The suite of biological changes that occur in later adulthood
Adult Stage
The third stage of life, involving the reproductive years and senescence
In both Bergmann's and Allen's rules, surface area plays a major role in how heat is conserved or dissipated. What happens in animals with greater surface area?
They are able to dissipate heat more rapidly
Prenatal stage in humans consists of:
Trimesters
True or False: Dark skin is associated with high UV radiation, which is a smaller latitude
True
True or False: People who live in cold environments have a relatively higher BMR
True
True or False: Some human groups share genetic markers that no other human population has
True
True or False: Human populations that engage in activities that stress the skeleton (walking, lifting, carrying) have bones with optimum density
True (bones that are not used become brittle and easier to break, bones used more frequently become stronger
The disease rickets, which affects bone mineralization, results from a deficiency in:
Vitamin D
Generally, how old are women when they experience menopause?
around 50
People who live in the areas of the world highlighted in red have adapted to these particular geographical conditions and are likely to:
be short
Bermann's and Allen's rules differ because Bergmann's rule pertains to _____ and Allen's rule pertains to _____
body size, limb length
The postnatal stage of adolescence includes:
development of secondary sex characteristics and interest in adult social, sexual and economic behaviors
The concept of race began
during the Renaissance