Biological Anthropology Overview

The study of humankind, exploring who we are and what it means to be human.

The study of human biology, its evolution, and variations, examining relationships between humans and other organisms.

The study of primates (monkeys, apes, and humans), examining their behavior, biology, and societies.

The study of human skeletons, bones, and teeth, focusing on their anatomy, development, and evolution.

The study of human evolutionary history, using fossils and artifacts to understand ancient humans.

The study of human remains from past societies, focusing on anatomically modern humans.

Walking upright on two legs, a key adaptation that evolved around 6 million years ago.

A systematic process of learning and refining knowledge about the natural world through facts, experiments, and observation.

A testable, educated guess that aims to explain a specific phenomenon.

An explanation based on a wealth of evidence from tested hypotheses, providing a comprehensive understanding of how or why something occurs.

A description of a universal and inevitable truth about the natural world, describing 'what' happens rather than explaining 'why'.

A systematic approach to gaining knowledge, involving observation, hypothesis formation, experimentation, analysis, and drawing conclusions.

Scientific research characterized by rigorous testing, strong evidence, peer review, and a commitment to objectivity.

Misleading claims presented as scientific findings, often lacking rigorous testing, relying on weak evidence, or intentionally promoting a specific agenda.

The gradual biological change in organisms over generations, driven by natural selection, leading to adaptation and sometimes the emergence of new species.

The process by which organisms with traits better suited to their environment are more likely to survive and reproduce, passing those advantageous traits to their offspring.

The presence of slight differences between individuals within a population, providing the raw material for natural selection to act upon.

A trait that enhances an organism's survival and reproduction in a specific environment.

The evolutionary process by which new species arise from a common ancestor, often driven by adaptation to different ecological niches.

A segment of DNA that carries the code for a specific trait, inherited in pairs, one from each parent.

A variation of a gene, determining different versions of a trait (e.g., blue eyes vs. brown eyes).

The molecule that contains the genetic instructions for building and maintaining an organism, providing a blueprint for life.

DNA provides the basis for biological variation, enabling natural selection to act upon inherited traits, driving evolutionary changes over time.

DNA is organized as a double helix, resembling a twisted ladder. Each strand is made of nucleotides, with Adenine (A) pairing with Thymine (T) and Guanine (G) pairing with Cytosine (C).

DNA strands are packaged into 46 chromosomes, 23 pairs. One chromosome in each pair comes from each parent.

A visual representation of an organism's chromosomes. It helps determine genetic traits, including sex (XX for females, XY for males).

Found in most body tissues (skin, blood, etc.), these cells contain a full set of DNA (diploid, 23 pairs of chromosomes). Their DNA is not passed on to offspring.

Sperm and egg cells, used for reproduction. They contain half the DNA (haploid, 23 chromosomes). Gamete DNA is passed to offspring.

Cell division for somatic cells that produces two identical diploid daughter cells for growth and repair.

Cell division for gametes that results in four unique haploid cells.

The exchange of genetic material during meiosis, increasing variation in gametes.

An allele that masks the expression of a recessive allele in determining a trait.

The genetic makeup of an individual (e.g., YY, Yy, yy).

Observable characteristics determined by the genotype.

DNA is read by mRNA, which copies the genetic code in the nucleus.

mRNA moves to a ribosome, where tRNA helps assemble amino acids into proteins based on the mRNA code.

Animals in colder climates tend to have larger body sizes compared to those in warmer climates. This helps them conserve heat better.

Animals in warmer climates tend to have longer limbs and extremities. This helps them radiate heat more efficiently and stay cool.

Melanin, a pigment in skin, protects against harmful UV radiation from the sun. Darker skin is more common near the equator where UV levels are high. Lighter skin evolved in regions with low UV to promote vitamin D synthesis.

Permanent, inherited traits that are passed down through generations and common within a population. Examples include skin color variations.

Traits developed during growth, influenced by the environment and not inherited. Examples include lung capacity in high-altitude populations.

Temporary, reversible changes in the body's functioning in response to environmental stimuli. Examples include sweating or shivering.

The study of teeth, their structure, and how they reflect diet, ancestry, and evolutionary history.

Traits developed for living in trees, such as opposable thumbs, flexible joints, and enhanced vision (e.g., depth perception).

Ability to eat a variety of foods, supported by generalized or specialized teeth and a range of dental formulas.

Extended childhoods with intense parental investment, enabling brain development and survival skills.

Groups primates based on physical similarities (appearance and complexity), but does not indicate evolutionary relationships.

Groups primates based on evolutionary relationships and shared ancestry, focusing on how species diverged.

Primitive primates like lemurs, with enhanced smell and nocturnal habits. They have a more ancestral set of features compared to other primates.

Advanced primates like monkeys and apes, characterized by excellent eyesight, larger brains, and social behavior.

Found in Central and South America, they have flat noses, prehensile tails, and primarily live in trees.

Found in Africa, Asia, and Europe, they have downward-facing nostrils, are often terrestrial (ground-dwelling), and have advanced dental patterns.

Traits shared by two species because they descend from a common ancestor, reflecting shared evolutionary history.

Traits that evolved independently in different species due to similar environmental pressures, not shared ancestry.

Traits shared by many species due to distant common ancestry, representing a feature present in the ancestor.

Traits that evolved after the last common ancestor, highlighting recent evolutionary changes and specific lineages.

The study of how fossils are formed and preserved, focusing on the processes that affect their preservation and discovery.

A fossilization process where organic materials are gradually replaced by minerals, preserving the organism's original shape and sometimes internal structures.

Rapid burial increases the chances of fossilization as it protects the organism's remains from decay and scavengers.

A method of dating fossils that establishes the sequence of events without providing exact ages, using the Law of Superposition.

A method of dating fossils that provides numerical dates or date ranges, using physical, chemical, or cultural properties.

A type of absolute dating that measures radioactive decay of isotopes in fossils or rocks, providing numerical ages.

A dating method that analyzes the growth rings of trees to establish timelines and date wooden artifacts.

This method uses the Earth's shifting magnetic field to determine the age of rocks based on their magnetic orientation.

Gradualism suggests slow, continuous evolutionary changes over long periods. Punctuated equilibrium proposes periods of rapid evolution followed by long periods of stability.

This hypothesis suggests that primates developed adaptations for life in trees, like grasping hands and good vision.

This hypothesis argues that primates evolved precise vision and hand coordination to hunt insects, highlighting their predatory nature.

This hypothesis suggests that African primates floated to South America on vegetation rafts, carried by ocean currents.

Hominins are distinguished by bipedalism (walking upright on two legs) and non-honing chewing (small, dull canines) due to a shift in diet and movement.

This early hominin, dating back 7-6 million years ago, shows a mix of primitive traits and early bipedal adaptations.

This hominin, dating back 5.8-4.4 million years ago, exhibits tree-climbing and bipedal traits, a smaller cranial capacity, and reduced sexual dimorphism.

A genus of early hominins dating back to 3.6 million years ago, known for bipedal adaptations, small brain size, and a mixed diet.

Lucy, an Australopithecus afarensis, reveals a mix of human-like and ape-like features, including a valgus knee for stability in walking, non-opposable big toes for bipedalism, and a bowl-shaped pelvis for upright posture.

Paranthropus, or robust Australopithecines, had larger molars, strong jaws, massive chewing muscles, and slightly larger brains compared to Australopithecus. Australopithecus, or gracile Australopithecines, had smaller teeth, jaws, and overall builds, and smaller brains.

The classification of early hominins is complex due to incomplete fossil records, debates among scientists, fossil variation, and overlapping features between species.

Early stone tools dating back to 2.6-1.6 million years ago, characterized by simple, rough designs and created using chipping stones to produce sharp edges.

Homo has a larger brain size, smaller teeth, flatter face, and a skeletal structure optimized for running and walking, while Australopithecines have a smaller brain, larger teeth, a more ape-like stature, and curved phalanges for climbing.

Homo shows advanced tool use, social cooperation, and control of fire, while Australopithecines exhibit basic survival behaviors with limited evidence of complex social structures or tool-making.

Larger brains offer enhanced cognitive abilities, better social behavior, and adaptability to diverse environments. However, they require high energy, pose risks during childbirth, and require a nutrient-rich diet.

A larger brain leads to cultural and technological development, enhanced communication and social organization, and better adaptability to environmental changes.

Homo habilis, meaning 'handy man', lived from 2.4 to 1.4 million years ago and is a key species in the transition from Australopithecines to Homo. They are known for a larger brain size and the creation of Oldowan tools.

Homo erectus, existing between 1.9 million and 110,000 years ago, was a major evolutionary milestone due to their larger brains, endurance adaptations, use of fire, and migration out of Africa.

Homo erectus likely had more complex social structures and communication, and mastered the use of fire for cooking, warmth, and safety, enabling them to adapt to colder regions.

Homo erectus created Acheulean hand axes, versatile tools for butchering, digging, and other tasks. The precision and planning required for these tools reflect significant cognitive advancements.

The mastery of fire significantly impacted Homo erectus, enabling them to cook food, improve their diet, keep warm, and expand their habitat into colder regions.

A field that applies anthropological methods to legal investigations, focusing on identifying individuals, determining causes of death, and reconstructing past events.

An injury that occurred before death and shows signs of healing, such as rounded edges and bone remodeling.

An injury that occurred around the time of death, often characterized by sharp edges, splintering, and fresh bone.

An injury that occurred after death, often seen as brittle, straight breaks with flaking and color differences.

Analyzing skeletal stress markers to understand the activities and occupations an individual performed during their lifetime.

Using stages of decomposition, such as rigor mortis, insect activity, and skeletonization, to estimate how long ago a person died.

Using growth and developmental markers like bone length and dental maturity to estimate a person's age under 20 years old.

Using degenerative changes, such as joint surface wear, to estimate a person's age over 20 years old.

Analyzing skeletal features like pelvic morphology and robusticity differences to determine a person's biological sex.

Creating a likeness of an individual's face using anatomical data from their skull and other skeletal remains.

Using DNA, primarily extracted from teeth or bones, to identify individuals or find familial relationships.

Using mitochondrial DNA (mtDNA), passed down maternally, to trace ancestry and identify remains when nuclear DNA is degraded.

The skeleton of Richard III, King of England, discovered in 2013, providing insights into his life, death, and historical portrayal.

A condition causing an S-shaped curvature of the spine, often beginning later in life.

Multiple severe injuries found on his skeleton, including skull fractures and rib and pelvic cuts, indicating a violent death in battle.

Modern humans, Homo sapiens, are characterized by their gracile bodies, smaller brow ridges, rounded skulls with larger brains, flat faces, and prominent chins. They exhibit advanced intelligence, complex tools, art, symbolism, and language abilities. They have developed diverse technologies, social structures, and symbolic expression, as exemplified by cave paintings and carvings.

Neanderthals possessed short, stocky bodies adapted to cold climates, with large nasal apertures for warming air and large infraorbital foramina for maintaining blood flow in the face. They had robust skeletons and large brains, slightly exceeding modern humans.

Neanderthals were skilled toolmakers associated with the Mousterian tool tradition and Levallois technique, displaying planning, visualization, and dexterity in crafting intricate tools.

Neanderthals engaged in burial rituals and symbolic behaviors, like creating art and using body paint or decorations such as pierced shells. Their hyoid bone structure and the presence of the FOXP2 gene suggest the possibility of speech.

Neanderthals created simpler tools for survival, like those associated with the Mousterian tradition, while modern humans developed more specialized and complex tools for hunting, carving, and art, such as atlatls.

Neanderthals used basic symbolic items, such as body paint and pierced shells, whereas modern humans created elaborate artwork, carvings, and more complex symbolic artifacts.

Neanderthals lived in smaller, more isolated groups, while modern humans formed larger, more interconnected social groups with advanced cultural practices.

The Out of Africa model proposes that modern humans evolved in Africa and then spread globally, replacing other hominins. Evidence includes older fossil and tool evidence in Africa compared to other regions, and the highest human genetic diversity found in Africa, suggesting an African origin.

The Multi-regional model suggests that modern humans evolved simultaneously in multiple regions from regional populations of Homo erectus, with gene flow maintaining species unity. Evidence includes fossil continuity across regions showing traits evolving locally into modern forms, and support for long-term gene flow between populations.

The Assimilation model combines elements of both Out of Africa and Multi-regional models, suggesting that modern humans evolved in Africa, migrated globally, and interbred with archaic populations such as Neanderthals and Denisovans. Evidence includes genetic data showing non-African populations carrying Neanderthal DNA and fossil and artifact overlap between modern humans and other hominins in Europe and Asia.

The Neanderthal Genome Project revealed that Neanderthals share 99.7% of their DNA with modern humans. Non-African populations today carry 1-4% Neanderthal DNA, with higher levels in Europeans and lower levels in Asians. This supports the Assimilation Model, confirming interbreeding between Neanderthals and early modern humans. It highlights the close relationship between them, sharing evolutionary history and some gene flow.

Global human expansion around 50,000 years ago was motivated by factors such as seeking new resources, adapting to changing climates, and exploring new territories. These motivations contributed to the successful spread of humans across diverse environments.

Homo floresiensis, nicknamed 'The Hobbit,' is an extinct human species discovered in Indonesia. Their small stature, unique skeletal features, and relatively recent existence suggest a complex history of human evolution and adaptation, particularly on islands.

Shared physical traits, such as facial features and skeletal characteristics, as well as genetic similarities, strongly link Native Americans and Asian populations, suggesting a common ancestral origin and migration route across the Bering Land Bridge.

The transition to agriculture around 10-12,000 years ago allowed for larger populations, division of labor, technological advances, and a stable food supply. However, it also led to environmental degradation, social inequality, malnutrition, and increased spread of diseases.

Agriculture led to changes in human anatomy and health, including skeletal changes, such as dental issues from softer diets, and signs of stress and malnutrition in bones. The shift towards sedentary lifestyles and reliance on certain food sources had both positive and negative impacts on health.