Independent Study
ANTH 101L: Biological Anthropology Lab
Course Notes and Assignments
Module 1 Course Notes (Chapters 1 and 17)
Chapter 1 – Introduction to Biological Anthropology
What is anthropology? And what is biological anthropology, in particular? Have you thought about it before?
Anthropology, in short, is the study of all people in all places and times. Studying people everywhere and everywhen. Anthropology (in the United States, anyway) is divided into four major subfields: cultural anthropology, archaeology, linguistics, and biological anthropology. Across all of these areas of study, we employ four approaches to research: holism, comparison, dynamism, and fieldwork. Of these, fieldwork is what you have likely heard about the most. Lab work aligns with fieldwork in that it provides hands-on application of the concepts.
Let me break this down a bit further. Cultural anthropology is the study of living cultures. Culture is the main way that we adapt to our environment (we are not polar bears packing on extra body fat and thick fur in preparation for winter . . . instead we invent shelters, means to heat them, and warm clothing). The main way cultural anthropology studies are conducted is through participant observation. This means researchers, after doing a huge amount of background research, are living among the people they are studying, interacting with them, observing them, and often participating in daily activities. This is fieldwork and often extends for many months at a time, sometimes a year or more. Archaeology, near and dear to my heart, is the study of past cultures through the things they leave behind. This means either their artifacts or, sometimes, their bodily remains. Artifacts are anything created or affected by humans, so, objects, roads, structures, storage pits, pyramids . . . these are all of interest to archaeologists. Linguistics is everything you ever wanted to know about language but were afraid to ask. Linguists study modern languages, ancient languages, languages that are written, languages that are spoken only, how language is acquired, how languages are similar and how they have changed over time. Finally, biological anthropologists are the body folks. They study how we are similar, how we are different, and how things have changed over time. Yes, we change physically but that is over long time-frames. Remember that culture is the main way we adapt to our environment, and cultural changes can happen very quickly. Each of these four major subfields has many many subspecialties. Some anthropologists talk of a fifth major subfield, though it really relates to each of the four so I don’t consider it a fifth subfield: applied anthropology. Applied anthropology is the practical application of any anthropological subfield to real-world issues. An example would include forensic anthropology, which is a subdiscipline of biological anthropology.
Biological anthropology (sometimes shortened to bioanth) has also been called physical anthropology. You will see many references to this and it’s often a factor of the time period the author learned it in school. Often physical anthropology is an older term, though both biological anthropology and physical anthropology are valid terms for the same thing. Biological anthropology has numerous subfields within it including: primatology (think Jane Goodall), paleoanthropology (looking at ancestors waaay back), molecular anthropology (looking at genetics and DNA), biological archaeology (examining human remains from archaeological settings . . . fascinating stuff), human biology (looking at modern adaptations and variations), medical anthropology (difficult to define succinctly but the application of anthropology to medical issues), and paleopathology (looking at usually skeletal pathology in ancient specimens).
Anthropology seeks to apply the scientific method. You should be familiar with it already, but if you are not here it is in a nutshell: essentially a researcher would make observations, decide on a testable hypothesis, test it, obtain the results, and revise the hypothesis as needed.
Chapter 17 (in the Appendices) – Osteology
This week please read Appendix A in the textbook.
Page 635 is a good reference for the complete human skeleton.
It is important to have a basic understanding of osteology (the study of human bones) since this is a critical part of the material examined in biological anthropology. This unit gives a good overview of the human skeletal system. One note of clarification: Some people confuse osteology with faunal analysis. While osteology is the study of human bones, faunal analysis is the study of animal bones, usually from archaeological contexts.
The human skeleton can tell us a lot about people right now, from a few hundred years ago, or from thousands of years ago. Soft tissues do not usually survive from the past (though there are certainly exceptions) but, because of their mineral content, bones preserve surprisingly well. Burial context and preservation is important and that is a whole other topic. For now, understand that we see very poor preservation in very acidic burial contexts.
As the text mentions, there is standardized anatomical terminology used to describe anatomical positions, features, directions, and movements.
The anatomical position (see p. 676) is the standard way of laying out a human body or skeleton so that no bones are twisted around, and directional planes are taken from this position. It is important to understand what anterior, posterior, distal, superior, medial, lateral, inferior, proximal, robust, and gracile (robust means what it sounds like, bigger and thicker; while gracile means thinner and leaner) mean. Also, understand what cranial skeleton vs. post-cranial skeleton indicates (head and everything below the head). Note the directions in Figure A.3 on p. 628. Pp. 629-630 and Figure A.4 give an explanation of bone structure and remodeling. Bones are generally considered one of five shapes including: long, short, flat, sesamoid, and irregular. There is a typo on p. 634. The fifth line of text should read “against the force of gravity, . . . “ Note the discussion of the axial vs. appendicular skeleton on pp. 634-5.
The text gives a good tour of the head and there are good illustrations on p. 637 Figure A.13 that will be worth referring back to this semester. Note the foramen magnum shown in Figure A15 and its position beneath the cranial base.
On p. 645 there is a brief discussion of teeth. Each tooth type has a particular shape and function.
The flat incisors in the front of the mouth are excellent for slicing into food, such as a piece of fruit or a vegetable. The canines (vampires, dogs, and cats have hyper-developed canines) are good for puncturing or grasping food for tearing. The premolars (sometimes called bicuspids) and molars are good for grinding and tenderizing food prior to swallowing. Teeth can be, and often have been, used for tools as well. We can learn a lot about an animal’s diet by looking at its tooth count and type.
Alligators have one kind of dentition, goats have another. Also note that human deciduous teeth (the baby teeth that fall out) are a bit different from our permanent teeth. Think about what that means for us and our diet. We’ll look at teeth a bit closer later.
The vertebral column is a fascinating stack of bones which support our upright posture, provide a framework for attaching ribs which provide protection for vital organs, and which is designed to flex as we locomote. There are seven cervical (neck), twelve thoracic (upper torso), five lumbar (lower back), five sacral –and these are fused (back of the pelvis), and three or four coccygeal (tailbone) vertebrae. Note that “vertebra” is the singular form, “vertebrae” is the plural form. Each type has typical morphologies specific to its region. The text has very good labeled illustrations. Note the different spinal curvatures that help maintain stability.
On pp. 651-2 there are a couple of typos. The text on p. 651 references Figure A.31 but there appears to be no Figure A.31. On p. 652 the text should read, “The humerus is the bone of the upper arm.” (Note, there is no “o” in humerus)
The appendicular skeleton (arms, legs, hands, feet) contains numerous long bones that are important in determining age at death, height, musculature, and often reveal signs of disease or injury.
The pelvic girdle is the most important site in a skeleton for determining sex. Please note that in anthropology, sex and gender are not necessarily the same things. Sex is biological and is determined by chromosomes (more on that in a later chapter) while gender is a socially constructed role, though that’s more in the domain of cultural anthropology than our study of biological anthropology right now. There are a few features in the pelvis that can also be used for helping to determine age at death, depending on how well preserved they are.
There is another typo on p. 658. The text should read, “There are two bones of the lower leg: . . . “ There is a brief discussion of adult skeletons vs. subadult skeletons and of comparative anatomy
also.
Module 1 Assignment
Please fill in the osteology of the skeleton and the skull worksheets found below and submit them.
Answer the following questions about the bones indicated on the diagram on the previous page using the correctly spelled scientific terms.
A. This is often one of the best preserved portions of a skeleton.
B. This bone supports strong muscles in the upper arm.
C. These support the torso and, working together with the other bones in this stack, give the
body stability when upright.
D. These two bones articulate with other bones at the elbow and the wrist.
and
E. This portion of the head articulates with the upper bones of the head near the ear.
F. These two bones articulate with other bones at the knee and at the ankle.
and
___________________
G. This entire circular structure is important for determining biological sex of a skeleton and
helps to support the internal organs.
H. This is the strongest bone in the body and is difficult, though not impossible, to break.
______________________
I. This little bone is not usually present in newborn babies but develops in the first couple of
years of life.
J. These bones articulate with the fingers and the bones of the wrist.
Use the correctly spelled scientific terminology to answer the questions below.
"Skull illustration, lateral view - Axial Skeleton Visual Atlas, page 17"byRob Swatskiis licensed underCC BY-NC 2.0
A. The angle of this bone is one method of determining biological sex from the skull within a
population. Its angle is an important feature of early hominins.
B. This is the general term for where two bones come together, usually forming a joint. We say
two bones here.
C. This paired bone is a major bone of the head and meets in a center line called the sagittal suture. It also forms part of the lambdoid suture at the posterior of the head.
D. This bone forms the lower portion of the lambdoid suture and figures prominently in
Neanderthals skulls.
E. The robusticity of this boney projection is another method of determining biological sex from the skull within a population and can be readily felt behind the ear.
_______________________
F. This bone forms the cheek bone.
G. This boney projection is well-developed in modern Homo sapiens sapiens, not so much in
early hominins.
H. This bone resides above the ear.
"Skull illustration, anterior view - Axial Skeleton Visual Atlas, page 9"byRob Swatskiis licensed underCC BY-NC 2.0
A. The bones of the top of the head meet in a midline connection here.
B. This boney area’s size is one method for determining biological sex from a skull within a
population and is quite prominent in Neanderthals.
C. This rounded area protects the eyeball.
D. This is where the upper teeth are found.
E. This is the lowest part of the skull and is where the lower teeth are found.
F. These prominent boney projections form. the cheek.
G. These little holes allow for the passage of nerves and blood vessels.
Module 2 Course Notes (Chapters 3 - 5)
Chapter 3 – Molecular Biology and Genetics
In Biological Anthropology, ANTH 101, we looked at the principles of inheritance including
Mendelian inheritance where we have single-gene recessive or dominant alleles. Remember that in this case heterozygous indicates the inheritance of two different alleles for a gene, while
homozygous indicates the inheritance of two of the same alleles for a gene. Mendel famously studied pea plants and noted a number of different characteristics for which he was able to
determine dominant and recessive traits. When a heterozygous gene carries a recessive and a
dominant allele, the dominant allele will be expressed in the phenotype. The same is true for a
homozygous gene carrying two dominant alleles. A homozygous gene carrying two alleles is
required for the recessive trait for that trait to be expressed. Examples of Medelian traits found in
humans includes mid-digital hair (hair on the middle segment of your fingers), tongue rolling (the ability to roll the sides of the tongue into a tube), earlobe attachment, interlocking fingers and
thumbs (placing the left thumb over the right is the dominant condition), earwax color, and a cleft chin (dimple in the chin). Remember in the Explorations online textbook we looked at a number of different inheritance patterns including incomplete dominance and codominance. There is also a
sex-linked inheritance pattern where a trait is carried on the X chromosome. Since females have two X chromosomes (XX), an allele on a single X chromosome will not necessarily be expressed or
expressed in full, whereas since males have an X and a Y chromosome (XY), if they carry the
proper allele, it will be expressed. This can have serious health consequences with diseases such as hemophilia, which is carried by females but is most commonly expressed in the male offspring.
Some members of Queen Victoria’s royal lineage in royal families in Europe experienced this devastating disease. You’ll read more about different modes of evolution in part of this week’s assignment.
Module 2 Assignment
Complete the Punnett Square assignment (below), the Gene Flow assignment, and the Genetics Discussion and submit them.
Punnett Squares:
Gene Flow Assignment:
In Biological Anthropology, ANTH 101, we looked at some of the ways allele frequencies change so we take a tangible view of what that might look like. For this assignment you will need a group of multi-colored candies or small pieces of paper about the size of a dime (think M&Ms or Skittles, or something like that . . . you can use crayons but that’s not as much fun). You need anywhere from 30-100 candies/colored pieces of paper and you need more than four colors but fewer than ten, your choice. Make sure your hands are clean and have a separate piece of paper for notes.
1. Place a piece of paper (regular notebook or printer paper is fine, this is not for notes) on your desk in front of you. Dump all the candies into one pile together and mix them up. Record how many total candies you have. The different colors represent different alleles. Randomly divide your pile into two equal groups (call one Group A and the other B) and set one aside. These groups are your gene pools. Record how many of each color you have in each group.
2. Draw two “islands” on your paper then randomly populate both islands with the candies from your group that you did not set aside (Group A). Count the numbers of each color on each island and record your results. These are your starting populations for these islands. Now push the candies from both islands together and mix them. You have introduced new genetic material and this illustrates gene flow, what happens when two populations experience any admixture of new alleles. Record your total numbers of each color in this newly mixed group.
3. Now randomly place your hand over top of this population and remove approximately a third of the pile (no need to count, just approximate a third of your pile and push it aside). Eat these candies (or share with your friends/family). You have just experienced a catastrophe of a natural disaster or disease. Record your numbers for the remaining group. How have your allele frequencies changed? Did you greatly reduce any one particular color? As your population numbers get smaller, you have a more limited gene pool from which to draw genetic material. This could potentially lead to health issues as the chances of deleterious genes being expressed increases.
4. Now set what remains of Group A aside and pull out your original Group B. Be sure you have recorded how many of each color you have for this group. Eat (or share) all of your favorite color of candies from Group B. This represents Natural Selection, because you selected them out of the population due to some particular trait (in this case, color).
Record how many of the eaten candies there were and how many remain of each of the other colors. This has again changed your allele frequencies and has removed (and represents a lack of) those alleles from your populations. The eaten candies might represent a hair color or an eye color, or perhaps lactase persistence (the ability to digest milk and milk products after childhood), etc.
5. Finally, push all of your candies from both groups together. Record your numbers (total and numbers of each color). Now randomly take one in every five candies and squish it a bit with your thumb. This represents random mutation, which may occur in DNA replication. This may not have a deleterious effect on the population or, on the other hand, it could reduce the “success” of that part of the population, meaning that segment of the population will not successfully reproduce and have fertile offspring.
This exercise has illustrated some of mechanisms of allele frequency change. Please type up your numbers and discuss how allele frequencies changed (or didn’t) with each step (minimum half a page of discussion).
Genetics Discussion
Final part of the assignment for this module:
Please write your responses to the question below. The more examples you can give, the better.
What are the ramifications of a service like 23andMe? What kind of information can an individual learn from genetic testing? Is this good or bad or ??? Who should have access to this information? Why? If it helps, you can visit the website of a genetics testing company to see what services they offer before answering these questions.
Module 3 Course Notes (Chapters 5 and 9)
Chapter 5 – Meet the Living Primates
This week read the chapter in the text to better inform. you for the primate assignment below. Your assigned primate depends on when you were born! Jan/Feb = human, Mar/Apr = chimpanzee,
May/June = orangutan, July/Aug = gorilla, Sept/Oct = ring-tailed lemur, Nov/Dec = baboon.
Chapter 9 – Early Hominins
Along with these course notes, take a quick look at the overview of bipedalism in the ANTH 101
Explorations text on pp. 327-330, especially the illustration in Figure 9.5 and the list in Figure 9.6.
Here we turn our attention to bipedalism, its associated biological morphology, and behavioral
changes it precipitates. What is bipedalism and why is it such a big deal in biological anthropology? Bipedalism is the act of walking on two legs as opposed to quadrupedalism, which is the act of
walking on four. Bipedality distinguishes humans from all other modern hominins in that we are the only ones who can locomote comfortably in a bipedal manner; indeed, we use habitual bipedalism
which means it is our most comfortable, efficient, and easiest method of locomotion. Certainly apes can and do use bipedalism at times but their gate is not smooth, and is more of a waddle from side to side. Also, it is not the most comfortable or frequently used form of locomotion among the apes.
We have talked about different anatomical parts of the skeleton and when examining fossils for signs of possible bipedality, we must look at specific areas of the skeleton for clues, often taking more than one feature into account.
The foramen magnum is located very differently in a bipedal human than it is in a quadruped such as a great ape. Even though apes spend a lot of time in a seated position, locomotion is frequently
quadrupedal which means the head needs to be held where the animals can comfortably see where they are going whether locomoting slowing or quickly. The foramen magnum of an ape, then, is
located fairly posteriorly which facilitates keeping the head in a horizontal orientation during
quadrupedal locomotion. The foramen magnum of a human, on the other hand, is located much more towards the center of the inferior portion of the skull in order to balance it atop the spinal column which is the optimum orientation for bipedalism.
The human vertebral column is S-shaped with a curve in the upper portion of the spine (the
cervical curve) and a curve in the lower portion of the curve (the lumbar curve). These two curves act as a giant shock absorber and keep the weight balanced over the knees and feet in a midline of a bipedal human. The vertebral column in an ape is straighter which causes the weight to be carried more forward when standing.
The pelvic girdle is short and broad in bipedal humans forming a bowl shape, and it supports the
internal abdominal organs. (see the illustration on the next page) The gluteal muscles attach to the
posterior surface of the ilia and help to stabilize the hip and maintain balance when one foot is off
the ground during a stride. The left gluteal muscles balance the left leg and hip while the right foot is striding and the right gluteal muscles balance the right leg and hip while the left foot is striding. The pelvic girdle of apes is very different. It is tall and narrow, and forces the center of gravity to the
anterior of the body. The gluteal muscles allow forward motion but are not positioned to balance the
animal in an upright position when one leg is off the ground so they cannot balance on one leg like humans can.
One other difference between a human pelvis and an ape pelvis is the size of the inlet or large hole in the middle. The inlet of an ape pelvis is quite large in comparison to that of a human. Ape infants easily pass through this inlet, which means that childbirth is much easier for an ape. The large inlet easily allows the passage of the infant ape whereas the smaller inlet in the human pelvis, which is a function of its shape, makes childbirth much more difficult in humans since the size of a human
infant’s head (the largest circumference feature of a human infant) is very close to the size of the
human pelvic inlet. On occasion, a human infant’s head is too large to pass through the mother’s pelvis which necessitates Cesarean delivery. This is thought to be an anatomical tradeoff for bipedality.
The angle of the femur and how it articulates with the top of the tibia at the knee is also different
from apes. Apes tend to have straight knee articulation whereas human bipeds tend to have the
knees angled inward to better balance the pelvis above the knees, this is known as the valgus knee. The foot also is different in that the ape toes (phalanges) are long for grasping (prehensile) and the big toe (hallux) is divergent, meaning it splays sideways to the medial aspect of the foot. The foot in the bipedal human has short phalanges with a large, non-divergent hallux that bears a great deal of weight. Along with the powerful calf muscles, the human hallux is used to propel the foot. Both ape and human feet have a transverse arch which runs medially to laterally, but only humans have a
longitudinal arch running from the toes to the heel. You can see evidence of this in your own foot if you look at footprints you leave with your bare feet in soil or as a wet footprint on a solid surface (such as after a dip in a pool or after getting out of the bathtub or shower).
So how does bipedalism change human behavior. over that of an ape? Well, habitual bipedalism
means that we spend less time in trees than apes do. Our feet and legs are not as well suited to
climbing trees as are the feet and legs of apes, and we do not brachiate on a regular basis (unless we spend a fair amount of time on jungle gyms). Apes are able to easily traverse branches in trees, often traveling from one tree to another through quadrupedal movement, using prehensile toes, leaping,
and brachiating. Humans, however, use habitual bipedalism and spend a vast majority of their time terrestrially. Advantages of bipedalism include the ability to carry things (objects and infants),
hunting since the hands are freed up to engage in hunting activities, gathering from higher terminal branches than from the ground level, thermoregulation since less of the torso is directly exposed to the sun and the head is elevated above the heat reflected from the ground, the ability to traverse long
distances using less energy since quadrupedal locomotion requires much more energy than
bipedalism, and surveillance of prey or predators from a higher location than from a quadrupedal elevation on the ground.