Language and Evolution M70 Midterm Study Guide

What are Hockett’s design features?

Characteristics used to describe communication systems and compare human language with animal communication.

Vocal-auditory channel

Spoken language is produced vocally and perceived by hearing; signed languages instead use a visual-manual channel.

Broadcast transmission and directional reception

Speech spreads outward, but a listener can determine the direction of the source.

Rapid fading

Spoken signals disappear soon after production; they do not remain audible.

Interchangeability

A speaker can produce and understand the same classes of linguistic messages.

Total feedback

Speakers can perceive and monitor their own speech while producing it.

Specialization

Language signals are specialized for communication rather than directly performing another physical action.

Semanticity

Linguistic signals are associated with meanings or referents.

Arbitrariness

Most word forms have no necessary natural connection to their meanings, such as dog versus perro.

Discreteness

A language has distinguishable units, such as the separate phonemes /p/ and /b/.

Displacement

Language can refer to people, places, times, or events not immediately present.

Productivity

Speakers can create and understand novel utterances using a limited set of elements and rules.

Traditional transmission

A specific language is learned through social interaction and passed across generations.

Duality of patterning

Meaningless sounds combine into meaningful linguistic units; these combine into larger expressions.

Prevarication

Language permits deliberately false, deceptive, or imaginary statements.

Reflexiveness

Language can be used to discuss language itself.

Learnability

People can learn additional languages beyond the language first acquired.

Hockett: Talking about tomorrow’s exam demonstrates what?

Displacement: the message is about an event outside the immediate present.

Hockett: Inventing a brand-new sentence demonstrates what?

Productivity: language users can form novel expressions.

Hockett: How do semanticity and arbitrariness differ?

Semanticity = signs convey meaning; arbitrariness = form-meaning pairings are usually conventional.

Hockett: How do discreteness and duality differ?

Discreteness = distinct units; duality = meaningless units combine to form meaningful units.

Are all Hockett design features exclusive to humans?

No. Some animals share individual features; human language differs in its broader combination and degree of these capacities.

Charles Darwin

Proposed evolution by natural selection: inherited variants affecting survival and reproductive success can change in frequency over generations.

Gregor Mendel

Investigated inheritance using pea plants and identified basic patterns of hereditary transmission.

Watson and Crick (1953)

Proposed the DNA double-helix model, building on key evidence from Rosalind Franklin, Maurice Wilkins, and others.

What are the four DNA bases?

Adenine (A), thymine (T), cytosine (C), and guanine (G).

Which DNA bases pair together?

A pairs with T; C pairs with G.

Gene

A DNA sequence that contributes to producing a functional product and can affect development or traits.

Allele

An alternative version of a gene or DNA sequence at a locus.

Genotype vs. phenotype

Genotype = genetic makeup; phenotype = observable characteristics influenced by genes and environment.

Dominant versus recessive allele (simple Mendelian case)

A dominant allele is expressed in a heterozygote; a recessive phenotype typically requires two recessive alleles.

Punnett square

A grid used to predict possible combinations of parental alleles in offspring.

Aa × Aa: genotype probabilities

25% AA, 50% Aa, 25% aa.

Aa × Aa: phenotype probabilities under complete dominance

75% dominant phenotype and 25% recessive phenotype.

Mutation

A change in DNA sequence; its effects can be beneficial, harmful, or neutral.

Natural selection

Process by which inherited variants differ in reproductive success, changing variant frequencies over generations.

Mutation versus selection

Mutation introduces genetic variation; natural selection acts on inherited variation.

Speciation

The evolutionary formation of distinct species or lineages, often involving reduced gene flow or reproductive isolation.

Epigenetics

Changes in gene regulation or expression that do not require altering the underlying DNA sequence.

Does one gene determine a person’s overall language ability?

No. Speech and language involve many genes interacting with brain development, learning, and environmental experience.

Hominin

A member of the human lineage after its split from the line leading to modern chimpanzees and bonobos.

Homo ergaster: region and period

Africa, especially East Africa; approximately 1.7–1.4 million years ago in the lecture.

Homo ergaster: key features and tools

Long limbs adapted to walking; often considered early African Homo erectus; associated with Acheulean/Mode II technology.

Homo erectus: region and period

Africa and much of Asia, including China and Indonesia; roughly 1.9 million–100,000 years ago in the lecture.

Homo erectus: key traits and evidence

Prominent brow ridge; widespread migration; Java Man and Peking Man; associated with Mode II/Acheulean tools.

Homo heidelbergensis: region and period

Europe and possibly Africa/Asia; approximately 700,000–200,000 years ago in the lecture.

Homo heidelbergensis: traits and tools

Relatively large brain and smaller jaws/teeth; Mode II tools and fire; often linked to Neanderthal ancestry, though classification is debated.

Homo neanderthalensis: region and period

Mainly Europe and western Asia; approximately 400,000–30,000 years ago in the lecture.

Homo neanderthalensis: traits and tools

Cold-adapted robust body, large cranial capacity, Mousterian/Mode III tools; interbred with Homo sapiens.

Homo sapiens: origin and age

Modern humans originated in Africa roughly 300,000 years ago and later spread widely worldwide.

Homo sapiens: migration in the course lecture

The lecture highlights a major dispersal out of East Africa around 50,000–45,000 years ago.

Which hominin is strongly associated with China and Indonesia?

Homo erectus; famous examples include Peking Man and Java Man.

Which hominin is strongly associated with Mode III/Mousterian tools?

Homo neanderthalensis.

Which hominin is often called early African Homo erectus?

Homo ergaster.

Was human evolution a simple straight line from one species to the next?

No. It involved branching lineages, overlapping time ranges, and some interbreeding.

Mitochondrial Eve

Most recent common ancestor of living people along unbroken maternal mitochondrial-DNA lines; not the first or only woman.

Y-chromosome Adam

Most recent common ancestor of surviving male Y-chromosome lineages along unbroken paternal lines; not the first man.

Must Mitochondrial Eve and Y-chromosome Adam have been a couple?

No. They need not have lived in the same place or time.

How is mitochondrial DNA usually inherited?

Maternally: a mother transmits mtDNA to her children.

How is the relevant non-recombining Y-chromosome region inherited?

Along paternal lines, typically from father to son.

Multiregional hypothesis

Modern humans developed through long-term evolutionary continuity across connected geographic regions, with gene flow.

Recent Out of Africa hypothesis

Modern Homo sapiens originated in Africa and dispersed outward, largely replacing earlier hominin populations.

Diffusion Wave hypothesis / Out of Africa Over and Over

Modification of Out of Africa: modern human traits spread through existing populations rather than only by total population replacement.

How does diffusion differ from strict replacement?

Diffusion allows traits to spread through contacts/interbreeding with established populations; strict replacement predicts populations are displaced.

What does genetic evidence generally support about modern human origins?

A predominantly African origin for Homo sapiens with some admixture with archaic humans such as Neanderthals.

Ritualized display

An often stereotyped or relatively inflexible communicative behavior; may be tied to a state such as aggression.

Intentional communicative signal (Tomasello)

A behavior flexibly chosen or adjusted to achieve a social/communicative goal.

Ritualized display versus intentional signal

Displays are generally less flexible; intentional signals are adjusted strategically to recipient and goal.

Phylogenetic ritualization

A behavior becomes a display across evolutionary generations through selection.

Ontogenetic ritualization

A gesture emerges through repeated interactions during an individual’s lifetime, as an abbreviated action comes to signal a goal.

Example of ontogenetic ritualization

An ape first physically pulls another’s arm, then learns a small reaching gesture is enough to request the response.

Intention-movement gesture

A shortened beginning of an action used to elicit a response that the full action would have produced.

Attention-getter gesture

A behavior used to attract the recipient’s attention, allowing further communication.

How might an ape show its gesture is intentional?

It monitors the recipient and may repeat, modify, or substitute the gesture when its goal is not met.

Tomasello: primate gestures versus vocalizations

Great ape gestures commonly show more flexible, individually learned, intentional usage than stereotyped primate vocal calls.

Why is the age of spoken language difficult to determine?

Speech itself does not fossilize; researchers must infer capabilities from indirect anatomical and archaeological evidence.

Hyoid bone: function

Supports/anchors tongue-related structures and is relevant to the pharynx, larynx, and articulation.

Human-like hyoid: Homo erectus example

Castel di Guido fossil, approximately 400,000 years ago in Lecture 5.

Human-like hyoid: Neanderthal example

Kebara 2 fossil, approximately 60,000 years ago in Lecture 5.

Does a human-like hyoid fossil prove full language?

No. It is evidence relevant to possible speech anatomy, not direct proof of syntax or linguistic behavior.

Larynx height and speech

The lower adult human larynx contributes to vocal-tract configurations that produce varied speech sounds.

Why is larynx height alone inconclusive evidence?

Other mammals have descended larynges, and fossil soft-tissue position cannot be reconstructed directly.

Cranial capacity and language

Increasing brain size can suggest neural capacity, but size alone cannot establish language abilities.

Why does bigger brain not automatically mean better language?

Brain organization, specialized networks, and connectivity also matter; Neanderthals could have larger skull capacity.

Early fire-use date in Lecture 3

Approximately 780,000 years ago, with evidence discussed from Gesher Benot Ya’aqov.

Early deliberate fire-making date in Lecture 3

Approximately 400,000 years ago; lecture cites flint/pyrite and hearth evidence.

How might fire have facilitated language evolution?

Provided opportunities for extended social interaction, cooperation, teaching, and activities after dark.

Does fire use prove language?

No. It suggests social and technological opportunities, not the presence of a specific language system.

Lower Paleolithic: general time range and tool industries

About 3 million–300,000 years ago in the lecture; Oldowan (Mode I) and Acheulean (Mode II).

Middle Paleolithic: general time range and tool industry

About 300,000–50,000 years ago; Mousterian/Mode III, strongly associated with Neanderthals.

Upper Paleolithic: general time range and industry

About 50,000–12,000 years ago; includes the Aurignacian, associated with Homo sapiens.

Mesolithic: approximate regional dates in the lecture

Middle East roughly 20,000–10,000 years ago; Europe roughly 15,000–5,000 years ago.

Oldowan / Mode I tools

Relatively simple stone cores and flakes; characteristic of early Lower Paleolithic technologies.

Acheulean / Mode II tools

More extensively shaped stone tools, especially bifacial hand axes; used by Homo erectus and heidelbergensis.

Mousterian / Mode III tools

Prepared-core and controlled-flake stone technologies; frequently associated with Neanderthals.

Aurignacian tools: period and association

An Upper Paleolithic industry associated with early Homo sapiens in Europe.

Why are complex tools relevant to language hypotheses?

Making them involves planning, sequencing, and possibly instruction, capacities that may overlap with language.

Why do sophisticated tools not prove spoken language?

Complex toolmaking can depend on skills and learning without demonstrating full linguistic grammar.

Jaw configuration and labiodentals: Blasi et al. (2019)

Proposed that diet-related changes in bite configuration made /f/ and /v/ easier or more frequent.

Labiodental consonants

Sounds made with lower lip against/near upper teeth, such as /f/ and /v/.