Evolution 4 Study Guide

However, some _____________ (the only ______________ with this trait) are lactose ________________, meaning they have the lactase ________________ trait and are able to produce ____________ throughout their ______________. This trait is mostly common in Northern ____________ and in ____________.

humans, mammal, tolerant, persistence, lactase, lifetimes, Europe, Africa

To ensure that you have enough Vitamin D, __________ Vitamin D production/_________________ (eat ______________); have ________________ sun exposure; consume _______ high in Vitamin D (like fish, eggs).

increase, consumption, supplements, moderate, foods

What was special about both the Maasai and the early Europeans that might explain why they each _______________ evolved this trait? Both are ______________ -- people who ________________ animals for food, and consumed ______ on a daily basis.

independently, pastoralists, domesticated, milk

Humans have very _______ hair on their skin, so they are more ______________ to damage from _____________. As a response to this, the early ancestors evolved _____________, the main determinant of _____ color, to ___________ UV light. The ____________ of melanin, however, and the _____________ of sunlight determine the ________________ of two very important vitamins, called ___________ and Vitamin D.

little, vulnerable, sunlight, melanin, skin, absorb, amount, strength, production, folate

The main selection _______________ for the evolution of skin color is the _____________ of ______ light, which varies by _________________. High latitude gets the _____ amount of UVB light (ie. Arctic, Antarctica). ________ latitude refers to Europe and southern Argentina areas, and __________ amounts of UVB light is present here. Low latitude refers to the ____________/tropical regions (ie. Africa, Asia), and this area gets _________ amounts of UVB light.

pressure, strength, UVB, latitude, least, mid, little, equator, high

When constructing ________ categories, we tend to focus on a very _____ (and not very _____________) traits that are the most _______. But these traits do _____ reflect overall genetic ____________ or _______________. For example, ___________ are more closely _____________ to Africans than Africans are to ____________ - who are also _______-skinned and have ___________ facial features.

racial, few, important, visible, not, similarity, relatedness, Europeans, related, Melanesians, dark, similar

These ________ categories, which have always been ill-defined, have _________ tremendously from one ________ to another. Races have been defined as ___________ of ___________ traits, ______________ tendencies, and _____________ attributes. These categories are not __________ and are changing over time.

racial, varied, place, collectives, physical, behavioral, cultural, static

Humans have ____________, however, this variation is not ___________ distributed - not all blacks are good at sports, not all Asians are good at math... and thus racial categories are simply ___________ constructs with no biological basis.

variation, racially, human

As some humans left ____________ and dispersed to _________ latitudes, there would have been selection for lighter or darker skin? __________! Because it ____________ the amount of Vitamin ____ that can be catalyzed from the little _____________ to _____ light, and Vitamin D is necessary for proper _______ development, _________ health, and a __________ immune system.

Africa, higher, lighter, maximizes, D, exposure, UVB, fetal, bone, strong

The fossil __________________ lived around _____ mya, and it is the earliest known phase of human evolution. Neither chimp nor human, there was an extension in the lower pelvis that showed that she was a _________________; and in the foot, a large ______ that stuck out to the _______ of the foot was seen, a surprising trait in a _________________ but not in primates. She is this peculiar ______________ of traits capable of ______________ on the ground, but also climbing abilities far superior to those seen in later Australopithecus and _______________. Looking at her structure, it is apparent that ______________ arose over ____ million years ago and _____________ tool use and the evolution of larger brains by at least a _______________ years; and that it evolved when our human ancestors were still living in ______________ and climbing trees, not in the __________________.

Ardipithecus, 4.4, climber, toe, side, hominid, mosaic, bipedalism, humans, bipedalism, 4, predates, million, forests, grasslands

According to fossil evidence, the major phases of human evolution are from ________________ ("Ardi" - ___________ with superior, non-hominid ______________ abilities, ____________ brain size, ____ stone tool use, and not adapted to the grasslands but to the _______________, which is where bipedalism evolved) to ___________________ ("Lucy" - ____________, ____________ brain, ____ stone tool use) to _____________ ("Olduvai 7" - ___________, _________ brain size that is bigger than those of modern chimps but not our modern size, and had stone _________ use abilities).

Ardipithecus, bipedal, climbing, small, no, woodlands, Australopithecus, bipedal, small, no, Homo, bipedal, large, tool

The fossil ______________________ lived around _____ mya, and it is evidence that ________ tool use did _____ evolve until early ____________ species since she herself did ______ have those capabilities. She is much more like a ___________ than a modern chimpanzee because of her _____ bone structures.

Australopithecus, 3.2, stone, NOT, Homo, NOT, human, hip

Folate is a member of the ___-vitamin complex. In _______-skinned people (ie. our earliest ancestors before turning dark) living in very ____________ sunlight areas, as ____ light hits their skin, _________ production is cut by ____ . _______ folate levels are particularly ________________ because it prevents normal _________________ development, thus lowering that organism's overall _________________. Thus, in areas where there is a lot of __________________ to the sun, people evolved _____________ skin since the _________ amounts of melanin will __________ the ________ light from penetrating ___________ in the skin cell to cut _________ levels down.

B, light, intense, UVB, folate, 1/2, low, bad, embryonic, fitness, exposure, darker, high, prevent, UVB, deeper, folate

_______________ evolution refers to changes in learned ______________, traditions, knowledge, _____________, and ways of living. These are major _______________ that allow humans to adapt to a variety of living _____________ without necessarily undergoing ____________ or biological change (ie. when early humans migrated to a _________ environment, they adapted by living in __________ and using ________ rather than evolving thicker hair and ______) *** ____________ AND _____________ CO-EVOLVE (ie. one affects another ==> ________________ animals led to spread of _______________ persistence).

Cultural, behavior, technology, adaptations, conditions, genetic, colder, caves, fire, fat, genes, culture, domesticating, lactase

According to ________ evidence, these human traits must have ______________ after the ______________ leading to ____________ split (____________) from the one that would eventually lead to modern __________________, our closest living relatives -- about ___ million years ago. This means that in the human's' ___________________ lineages, these _______________ characteristics arose independently between ______ million years ago (when the earliest human - Homo with these _____________ existed) and _________ million years ago (when the ____________________ and human lineages split).

DNA, evolved, lineages, humans, diverged, chimpanzees, 7, individual, derived, 1.8, characteristics, 7, chimpanzee

Modern humans (_________ ____________) were _____ the first to make it out of Africa. The species Homo __________ gave rise to ________________, Denisovans, and Homo floresiensis, all of whom escaped from Africa ___________. Since they were already _____________ in other parts of the world, these species then overlapped and ______________ with ___________ ___________ (that left ___________). As a result of this interbreeding between _______________ and Homo sapiens, _______________ and Asians were left with ___% to 4% of Neanderthal DNA, while sub-Saharan _______________ had ______ at all because their modern human ancestors (African Homo sapiens) did _____ migrate to Eurasia. Therefore, no amount of Neanderthal DNA was introduced into their _________ pool.

Homo sapiens, NOT, erectus, Neanderthals, before, situated, interbred, Homo sapiens, later, Neanderthals, Europeans, 1, Africans, none, NOT, gene

The fossil ___________ Olduvai 7 lived around _____ mya, and it is evidence that __________ tool use appeared near this time and in this __________ of human evolution.

Homo, 1.7, stone, phase

_______________ protects against skin cancer. However, organisms have ____ evolved melanin in response to skin _____________ scares -- they've only ___________ more or less ____________ in response to factors such as __________ and Vitamin _____ production. Unlike ______ folate levels and vitamin D _____________ which affect ___________ and are selected ___________ because the offspring don't ____________/have problems/people can't reproduce, skin __________ doesn't affect your _____________ because it happens ______________ in life, usually _______ you've already _________________ and passed down.

Melanin, NOT, cancer, evolved, melanin, folate, D, low, deficiency, fitness, against, survive, cancer, fitness, later, after, reproduced

__________ color has been the primary trait used to assign people to different "_______" (along with other __________ characteristics).

Skin, races, physical

______________ tools allow early humans to _________ first with scavengers and then with _______________. They broaden their diets and ultimately their _______________ range, leaving ____________. In fact, evidence supports the hypothesis of a recent African ____________ of all modern ______________. Human _____________ out of Africa generally involved __________ groups breaking off from the original population, called the _______________ effect. Because of this, Africans have more _______________ diversity than ______-Africans. Outside of Africa is simply a ____________ of diversity.

Stone, compete, predators, geographic, Africa, origin, humans, dispersal, small, founder, genetic, non, subset

Race, although unreal, has very real impacts on biology, especially in health. ____________ inequities (_________ racism) and _________________ result in _____________ in health outcomes in socially defined groups of people. For example, different "races," as a result of racism, have different access to _________ care, chronic __________, and ______-_________, which impacts the way their ____________ and ___________ systems develop.

Structural, systematic, discrimination, differences, health, stress, self image, bodies, immune

White skin does not equal superiority as black skin does not equal inferiority! It's simply a reflection of ______________.

ancestry

Why are some people lactose tolerant and others not? It depends on _________________. People whose _______________ lived in these ______________ are more likely to be ____________ ____________, simply because all of our current genetic _______ are a result of _______________ on our ancestors' _________.

ancestry, ancestors, populations, lactose tolerant, traits, selection, traits

Skin __________ is caused primarily by: _____________ light ___________, either from the _______ or from ________________ beds. ______-skinned individuals, with hazel or blue eyes, and people with blond or red hair are particularly ________________. The problem is worse in areas of high elevation or near the ____________ where sunlight exposure is more __________, and thus, more _______ light can cause _________ damage ⇒ ____________ ==> cancer!

cancer, ultraviolet, exposure, sun, tanning, light, vulnerable, equator, intense, UVB, DNA, mutations

In biology, there is only one real _______________ for humans: ___________ sapiens sapiens. And race, in biology, is a term used to identify ________________ of the ________ species with relatively ________ genetic _______________ (with not enough ___________ to be called ______________). However, it is impossible to even divide humans into ____________ races because humans are so ___________ genetically.

category, Homo, populations, same, small, differences, variation, subspecies, biological, similar

Vitamin D is made in skin cells from ______________, catalyzed with the help of ________ light. It helps to absorb ______________ and deposit in _________, an essential function in ____________________-- development. In ________-skinned people living in very ________ sunlight areas, as UV light hits their skin, most of it is _____________ by their melanin, and very little escapes into the skin cells to _____________ the creation of Vitamin ____. Therefore, they are at a higher risk for Vitamin D ____________. Thus, in areas where there is very _____ exposure to the sun, people evolved ___________ skin since the _________ amount of melanin will ensure that _______ UVB light _________________ the skin cells so that more Vitamin ___ is catalyzed.

cholesterol, UVB, calcium, bones, embryonic, dark, little, absorbed, catalyze, D, deficiency, little, lighter, little, more, penetrates, D

Why is this an example of _________________ of genes and culture ⇒ how did dairying drive the ____________ of the lactase persistence mutations? The _____ of milk ______________ for this trait because it provided an evolutionary ________________ in these pastoral locations. Since milk is very ______________ and _____ rich, is relatively not ______________ and reduces __________ to pathogens, and in a ___________ situation where only milk is available -- it can help the organism to ________________, there is VERY strong ____________ for this trait because, in these ________________, individuals with lactase __________________ are more likely to ____________ and reproduce. In _____-_______________ populations, however, this mutation provides no selective ________________ and is not maintained by __________________, so it is weeded out.

coevolution, spread, use, selected, advantage, protein, fat, contaminated, exposure, famine, survive, selection, populations, persistence, survive, non, dairying, advantage, selection

In addition to fossil evidence supporting human evolution, so does molecular evidence! First of all, although humans share a ______________ ancestor with chimps and other ______________, only _____________ beings (Homo sapiens) have ___ chromosomes whereas all the other primates have ____.

common, primates, human, 46, 48

By __________________ the lactase gene across tolerant and __________________ people, no ____________ differences were found in the _____________ region of the gene -- the section that coded for the ____________. However, in both the Maasai people in _________ and in the ______________, ____ different regulatory ________________ were present on Chromosome ___ around the gene that turned the gene _____ even after ________________, thus allowing both groups to have the lactase ___________________ trait.

comparing, intolerant, genetic, coding, protein, Africa, Europe, 2, mutations, 2, ON, weaning, persistence

An example of _________________ evolution - Both the African and Northern ____________ populations developed the same __________________ (lactase ______________) because both faced similar _______________ pressures (ie. the _____ of milk). In both populations, the use of _______ and ___________ of animals ____________ for the lactase ________________ trait because those with this trait were more likely to _____________ and ______________. As a result of this, over time, the _____________ of lactase __________________ increased in the populations.

convergent, European, phenotype, persistence, selection, use, milk, domestication, selected, persistence, survive, reproduce, frequency, persistence

Human ________________ evolution is sometimes called __________________ because these developed traits are ____ passed down or based ______________; it can be ______/gained due to use or ___________.

cultural, Lamarckian, not, genetically, lost, disuse

Human _____________ evolution/________________ has ______________ selection ________________ acting on humans and ____________________ for _________________ that increase evolutionary _______________. Before, there were many __________________ that used to kill people; there was __________ selection ______________ these individuals and selection for _____________; however, now that we're _______________ these people/they're _____________ and even reproducing, the ______________ for these diseases have actually __________________ (ie. hemophilia). Qualities that ________________ evolutionary fitness aren't as _________________ anymore - you don't need to be the Hulk to survive Siberia, in other words.

cultural, technology, relaxed, pressures, selection, qualities, fitness, diseases, strong, against, resistance, treating, surviving, frequency, increased, increase, important

Vitamin D _______________ is widespread in the US Risk factors include: ______ of exposure to ____________ amounts of UVB light (indoor lifestyles, use of sunscreen), and having ____________ skin (blocks _______ light so _______ light enters to catalyze Vitamin D production).

deficiency, lack, adequate, darker, UVB, little

Humans are ______________ from the _________ most recent common ancestor (that lived ____ million years ago in __________) as the _____________. Despite this, humans have three key features that distinguish them from their other ___________ relatives: ________ brains, walking on _______ legs instead of four (_______________), and the way humans use their _______ hands to make ___________ (ie. _______-making ability).

descended, same, 7, Africa, chimpanzees, primate, big, 2, bipedalism, free, tools, tool

Cultural evolution is _________________ from _____________ evolution because it's not _________________ based or caused by _________________ such as mutations, _______ flow, and _____________ selection. Rather, it is a ________________ characteristic. Also, it is different from biological evolution because it is a _________ adaptation (_________ time-scale) that does not require multiple ______________ to pass. Lastly, it's different from biological evolution because it _____________ new, unique ________________ (ie. technology), not necessarily _______________ amongst the phenotypic ______________________ present in the population.

different, biological, genetically, mechanisms, gene, natural, learned, quick, short, generations, creates, adaptations, selecting, variation

Our ____________ ancestors had ______ skin just like chimpanzees. When the early humans moved from the rain forest to the African _______________, they had to cope with _____ exposure to the __________ and had to work ____________ to get _______. Since mammalian brains are particularly _______________ to overheating, the ancestors developed a better cooling ____________ -- ________, which dissipates _______ through ________________. Through the process of ___________ selection, the _______ sweat glands present in the earliest human ancestors evolved to over more than __ million _____________, allowing the humans to be more ______________to the heat and thus forage for more food, _____________ and reproduce.

earliest, fair, savanna, more, sun, harder, food, vulnerable, system, sweat, heat, evaporation, natural, 2, glands, resistant, survive

Instead, during the _______________ of the ____________ that led to modern humans only, chromosome _____ must have gotten ______________ together with another ________________ to give only 23 chromosomes. This can be tested by examining the __________________ for a fused chromosome, which, if found will reveal that __________ and humans are descendants of the same most recent common _______________ with ____ chromosomes.

evolution, lineage, 24, fused, chromosome, genome, chimps, ancestor, 24

In addition, extensive "_______ _______" (intermixing) throughout human __________ has prevented significant genetic ____________ from accumulating in any population since it prevents ______________ ______________from occurring, and this is needed for the ________________ of different _____________ traits. So there really isn't enough ______________/traits exclusive to a "________" that can ___________ groups of people

gene flow, history, differences, reproductive isolation, accumulation, genetic, differences, race, classify

Bottom line: There is no _______ or _______ that ____ people of a certain "race" have, that ____________ else has (as per the social definition of race). There is no _____________ or genetic basis for the ___________ we create. Thus, there is no genetic __________ that is unique to only ______ group; no specific racial ________ or _________ patterns or ____________ traits (such as ________________, character, athletic ability, musical talent) that only ______ group possesses.

gene, trait, ALL, NOBODY, biological, divisions, sequence, one, gene, structural, complex, intelligence, one

There are no ____________ or ____________ characteristics that can define ____________ or ___________ belonging to a certain socially defined _________ group. For example, since humans cannot be naturally grouped into _______________ categories because there's only ____________ variation (and ______ amounts of it), even in skin color: there is a lot of ____________ of ______ color within people of a particular _________ or ethnic group, and significant overlap of ________ color among people from ____________ groups. Thus, no traits = ______ people from the race.

genetic, physical, anyone, everyone, racial, racial, gradual, tiny, variation, skin, racial, skin, different, ALL

_______________ and _____________ are still important. For example, you might have a ____________ probability of carrying a particular ____________ depending on the ______________ origin of your _______________. However, these patterns ___________ be accurately applied to socially constructed "_______" that are genetically __________________ (different from each other).

geography, ancestry, higher, allele, geographic, ancestors, cannot, races, heterogeneous

As some hominids lost body _______, there would have been ____________ for lighter or darker skin? _________! Because it protects the ___________ reserves from the intensity of the _________ light, and folate is necessary for proper _______ _________________. This means that skin color evolved from ______ to whatever _____ color is _____________ in an environment.

hair, selection, darker, folate, UVB, fetal, development, dark, skin, suitable

Humans are remarkably _____________________ (genetically similar) as a ________ and have very little genetic ____________, probably due to a genetic ______________ -- meaning, there isn't enough ________________ between _______________ of people to call them "______." (as per biology definition!)

homogenous, species, variation, bottleneck, variation, populations, races

V: Some ___________ were already ____________ tolerant due to random ____________. I: Lactase persistence is an _______________ trait, caused by a _____________ mutation that changes the _____________ of the lactase gene. S: In areas where humans had ________________ animals (ie. Europe and parts of Africa) and used _________ on a daily basis, humans with lactase ______________ were more likely to __________ and ______________, especially in times of __________. T: Over _______________, the ______________ of lactase ______________ ____________________ in these populations.

individuals, lactose, mutations, inherited, regulatory, expression, domesticated, milk, persistence, survive, reproduce, famine, generations, frequency, persistence, increased

When humans and other _______________ are __________, the cells in the _____________ produce _______________, an enzyme that breaks down ________________, a carbohydrate component found in ___________, into galactose and glucose, which can then be used for _____________. In most ____________, however, the _______________ of lactase stops after ______________, when the baby no longer drinks _______ and the gene is ______________ from _______________ itself. This is called lactose _________________, a largely dominant trait.

mammals, babies, intestines, lactase, lactose, milk, energy, humans, production, weaning, milk, prevented, expressing, intolerance

A common ___________________ for the loss of the ____th chromosome is that it was ______________ out or went missing. However, this is _____ possible because a loss of a _____________ trait like that would be strongly _______________ against, meaning the organisms with that missing ________________ (from a pair) would not even make it past ______________ development and ___________ to reproduce.

misconception, 24, tossed, NOT, critical, selected, chromosome, embryonic, survive

Many people don't understand the relationship between humans and other primates -- they may say that humans evolved from ________________, which is ____ true because an organism cannot evolve from something that is ______________. Chromosome ___ shows that ___________ and humans shared a most recent _____________ ancestor that had ____ chromosomes, that diverged into two separate _______________. Each of these lineages then ______________ unique characteristics that distinguished ________________ from its primate relatives.

monkeys, NOT, present, 2, chimps, common, 48, lineages, evolved, humans

At the _____, chromosomes have special _______ sequences, called ______________. Near the ________, they have _______________. If, in the _________________ leading to us, ______ primate __________________ got stuck together (ie. chromosome 24 got stuck to chromosome 2), you'd have a ____________________ with ____ telomere in the ________________ and a chromosome with two _____________________ . This physical characteristic is shown in chromosome number _____ --"it emerged as a result of head-to-head fusion of two "chromosomes that are still _________________ in other primates."" This means that the human's ancestor once had _____ pairs of chromosomes, but during their ________________ evolving lineage, _____ pair fused with one another to give only _____ chromosomes.

tips, DNA, telomeres, center, centromeres, lineage, 2, chromosomes, chromosome, 1, middle, centromeres, 2, separated, 24, independently, 1, 23

Lactase persistence is the ____________. Lactose ____________ is the HUMAN. ____________ milk does _______ cause the mutations. Lactase persistence is ________ caused by a mutation in the lactase __________, but in the ______________ area of that gene.

trait, tolerance, drinking, NOT, NOT, gene, regulatory

Stereotypes - the belief that a set of _________ belong to an __________ group of individuals (It is an attitude of _________ that results from seeing _________ as ________________ of groups, and an unwillingness to recognize people as ______________), while racism - the belief that certain ___________ are more or less ____________ to another (Racism may be put into practice in the form of discrimination or _____________).

traits, entire, prejudice, people, representative, individuals, groups, superior, violence