# Bioarchaeology

History I · Archaeology · https://tryals.app/learn/history-i/bioarchaeology

## The Body as Its Own Document

A skeleton is a written record in bone. **Bioarchaeology** reads it—reconstructing how a person aged, ate, worked, sickened, and moved—recovering the health and demography of whole populations that left no census.

| Question | Where the answer lives | Reliability |
|---|---|---|
| **Age at death** | Tooth eruption/wear; bone fusion | High in young, coarse in old |
| **Biological sex** | Pelvis shape; skull robusticity | High for adults; poor for kids |
| **Stature** | Long-bone length via regression | Good |
| **Disease/injury** | Lesions, healed fractures, wear | Only bone-marking traces |

Age reads sharply in the young via tight schedules, but blurs in adults. Sex determination leans on the pelvis, reshaped by childbirth, and fails before puberty because those differences have not yet developed.

## Chemistry: Diet and Origins

Bone chemistry preserves biography that shape cannot. **Carbon isotopes** distinguish diets, tracking whether staples were C3 plants like wheat or C4 plants like maize. **Nitrogen isotopes** rise with trophic level, revealing meat consumption and the nitrogen spike of breastfeeding.

**Strontium and oxygen isotopes**, locked into tooth enamel in childhood from local water and rock, reveal **where a person grew up**. A skeleton buried in one region with another region's isotopic signature is a **migrant**.

> **The osteological paradox:** A skeleton with **healed** lesions belonged to someone whose body fought the illness and lived. Someone who died fast shows **no** lesions. A cemetery full of lesions can mean a **healthier**, more resilient population, not a sicker one.

## Practice questions

8 of this lesson's 12 practice questions, with answers. The full set is in the app.

### 1. Sort each isotope by what it primarily reveals.

**Answer:**

- Diet (what they ate): Carbon δ¹³C: C3 versus C4 plants, Nitrogen δ¹⁵N: trophic level, meat and fish, Nitrogen spike of a breastfeeding infant
- Origin (where they grew up): Strontium in tooth enamel, Oxygen in tooth enamel, Enamel signature matching a distant bedrock

**Why:** Carbon and nitrogen read the plate; strontium and oxygen read the map. Two chemistries, two utterly different biographies, sometimes from the same tooth.

Page: https://tryals.app/practice/history-i/bioarchaeology/sort-each-isotope-by-what-it-primarily-reveals

### 2. A cemetery with many skeletons showing healed disease lesions must have been a sicker population than one with few lesions.

**Answer:** False

**Why:** The osteological paradox: healed lesions mark survivors whose bodies fought and remodeled. Those who died quickly leave no lesions. More visible disease can mean a _tougher_ population, the bone’s meaning is never self-evident.

Page: https://tryals.app/practice/history-i/bioarchaeology/a-cemetery-with-many-skeletons-showing-healed-disease-lesions-must

### 3. A cemetery shows high infant mortality and, among adults, unusually good health. Why might that be a statistical artefact rather than a finding?

A. Because the sample is too small to support demographic conclusions
B. The osteological paradox: the dead adults are the survivors
C. Because health cannot be assessed from skeletal remains at all
D. Because infant bones preserve poorly and are underrepresented

**Answer:** B. The osteological paradox: the dead adults are the survivors

**Why:** Lesions record survival long enough to remodel bone, so the sickest may die unmarked and the marked may be the robust, selective mortality inverts the reading. Wood and colleagues named the paradox in 1992, and it reframed a century of palaeopathology as evidence about who died rather than how people lived.

Page: https://tryals.app/practice/history-i/bioarchaeology/a-cemetery-shows-high-infant-mortality-and-among-adults-unusually

### 4. Order these skeletal age markers from the youngest age they appear to the oldest.

**Answer:**

1. First baby teeth erupt (infancy)
2. Permanent molars come in (childhood)
3. Long-bone growth plates fuse (late teens–twenties)
4. Cranial sutures and joint surfaces show wear (mature adult)

**Why:** The body ages on a schedule: teeth, then fusion, then wear. Tight and readable in youth, the schedule blurs into ranges as adulthood wears on.

Page: https://tryals.app/practice/history-i/bioarchaeology/order-these-skeletal-age-markers-from-the-youngest-age-they-appear-to

### 5. A skeleton shows no disease lesions at all. Why does that NOT establish that the person was healthy?

A. Because disease lesions are usually destroyed during burial
B. Because most diseases affect soft tissue only and never reach bone
C. Because lesions take time to form, and acute death leaves none
D. Because the skeleton was too fragmentary for lesions to be visible

**Answer:** C. Because lesions take time to form, and acute death leaves none

**Why:** This is the osteological paradox: the apparently healthiest skeletons may be the frailest individuals, who died too fast to develop lesions. Absence of evidence inverts here.

Page: https://tryals.app/practice/history-i/bioarchaeology/a-skeleton-shows-no-disease-lesions-at-all-why-does-that-not

### 6. Match each isotope system to its headline result.

**Answer:**

- Carbon (δ¹³C) → C3 versus C4 staple crops
- Nitrogen (δ¹⁵N) → How high on the food chain
- Strontium → Childhood geology, hence origin
- Oxygen → Childhood climate and water source

**Why:** Four isotopic dials — two for the diet, two for the homeland — reading a life the skeleton’s shape alone could never disclose.

Page: https://tryals.app/practice/history-i/bioarchaeology/match-each-isotope-system-to-its-headline-result

### 7. Which conclusions can bioarchaeology reasonably support from a well-preserved cemetery?

A. Patterns of healed injury suggesting hard labor
B. The exact spoken language of the population
C. The presence of first-generation migrants
D. Shifts in diet as a new staple crop arrived

**Answer:** A. Patterns of healed injury suggesting hard labor; C. The presence of first-generation migrants; D. Shifts in diet as a new staple crop arrived

**Why:** Diet shifts (carbon), migration (strontium), and labor stress (fractures, joint wear) all leave physical traces. Language leaves none in bone, that needs texts or inscriptions.

Page: https://tryals.app/practice/history-i/bioarchaeology/which-conclusions-can-bioarchaeology-reasonably-support-from-a

### 8. A skeleton shows enamel hypoplasia lines and a healed fracture. Why do the two together say more about this person’s life than either alone?

A. Because both are caused by the same nutritional deficiency
B. Because together they allow the age at death to be calculated precisely
C. Because one records stress survived and the other care received
D. Because only individuals who died young show either mark

**Answer:** C. Because one records stress survived and the other care received

**Why:** A healed fracture is evidence of other people: a badly injured person survives only if fed and sheltered. Read with the childhood stress lines, the skeleton documents a group.

Page: https://tryals.app/practice/history-i/bioarchaeology/a-skeleton-shows-enamel-hypoplasia-lines-and-a-healed-fracture-why