BIO A01 - Lecture 5: Darwin & Evolution

Vocabulary practice flashcards covering Charles Darwin's life, influences, Beagle voyage discoveries, and the foundations of evolutionary theory from BIO A01 Lecture 5.

Thomas Huxley's Evidence as to Man's Place in Nature (1863)

An 1863 scientific work presenting comparative anatomical drawings of ape and human skeletons to demonstrate the evolutionary affinity between humans and higher primates.

Sexual Selection

A mode of natural selection that consistently favors traits that increase an individual's access to reproductive opportunities.

Constraints on Natural Selection

Four key principles explaining why selection cannot craft perfect organisms: selection acts only on existing variants; evolution is limited by historical constraints; adaptations are often compromises; and chance, natural selection, and the environment interact.

Al-Jahiz

An Islamic scholar ($781\text{--}869\text{ CE}$) who wrote Kitāb al-Ḥayawān (The Book of Animals), proposing that species develop new traits for survival under varying environmental pressures via divine guidance and that biological fitness is essential to an animal's innate struggle to live.

Kitāb al-Ḥayawān

The Book of Animals, written by pre-Darwin Muslim scholar Al-Jahiz, outlining how animals develop adaptations and defense mechanisms against predators in order to maintain nature's order.

Natural History

The biological study of organismal form and variety in natural environments, rooted in ancient Greek philosophy and early classification systems such as Aristotle's in the 300s BCE.

Natural Theology

A historical scientific philosophy that sought to catalog and examine living organisms to honor God's creation, which ultimately generated evidence showing that species changed after their origin.

Taxonomy

The formal biological classification of organisms, originally pursued in European natural theology for the 'greater glory of God.'

Biogeography

The study of the worldwide spatial distribution of organisms, which raised critical challenges to the concept of static, unchanging species during global exploration.

Comparative Morphology

The comparative study of anatomical structures across different lineages that reveals deep structural similarities and shared origins among morphologically divergent organisms.

Vestigial Structures

Rudimentary anatomical structures preserved in modern organisms that have lost their ancestral utility and serve no current function.

Stratification

The horizontal layering of sedimentary rocks, wherein different strata contain distinct fossil assemblages indicating past extinctions and temporal changes in Earth's biota.

Paleobiology

The branch of biology dedicated to studying ancient organismal forms preserved in the fossil record.

Catastrophism

A geological concept asserting that sedimentary rock strata and fossil distributions formed primarily through sudden, violent catastrophes rather than gradual processes.

Principle of Use and Disuse

Jean-Baptiste Lamarck's proposed evolutionary mechanism stating that an organism develops or reduces body parts through use or disuse during its lifetime and passes these acquired modifications to its offspring.

Robert Grant

A marine invertebrate zoologist in Edinburgh who mentored Charles Darwin; Grant was a freethinker and supporter of Lamarckian evolution who believed complex life forms evolved from simple ancestors.

John Edmunstone

A freed Guyanese taxidermist in Edinburgh who spent many hours instructing Charles Darwin in bird preservation techniques and solidified Darwin's lifelong anti-slavery abolitionist convictions.

Professor John Henslow

A Cambridge botanist and close friend of Darwin who urged him to read Alexander von Humboldt's explorations and recommended Darwin for the naturalist position aboard HMS Beagle.

Adam Sedgwick

A Cambridge geology professor who introduced Darwin to field stratigraphy, Earth history, and the concept of deep time prior to Darwin's graduation in 1831.

Captain Robert FitzRoy

The Royal Navy officer commanding HMS Beagle who selected Charles Darwin as a traveling gentleman companion and naturalist for a hydrographic survey of South America.

HMS Beagle

A British naval survey vessel ($30\text{ m} \times 8\text{ m}$, carrying $73$ people) on which Darwin circumnavigated the globe from $1831$ to $1836$, a five-year voyage instead of the planned two.

Megatherium

An extinct South American giant ground sloth whose large skeletal fossils were collected by Darwin, showing distinct anatomical relationships to modern tree sloths.

Glyptodon

An extinct South American giant armadillo fossil that led Darwin to propose that extinct and living species in the same geographic area share a genealogical lineage.

Principle of Succession

The observation that fossil forms and existing modern taxa in the same geographic region share close morphological resemblances, reflecting evolutionary continuity in that area.

Chelonoidis nigra

The giant Galápagos tortoise (formerly Testudo elephantopus), weighing up to $450\text{ kg}$ ($920\text{ lbs}$) and living over $100$ years, which displays island-specific shell morphology adapted to local vegetation.

Galapagos Cormorant

The only flightless cormorant species in the world, having evolved reduced, non-functional flight wings while adapting to marine diving in the Galápagos archipelago.

Marine Iguana

A lizard species endemic exclusively to the Galápagos Islands that grazes underwater on marine algae.

Thomas Malthus

An English economist whose 1798 treatise An Essay on the Principle of Population argued that human populations double every $25$ years while food resources remain limiting, inspiring Darwin's concept of an organismal struggle for existence.

Artificial Selection

The deliberate selective breeding of domesticated animals and crops for desired traits, used by Darwin as empirical evidence that selection can systematically modify species forms.

Annie Darwin

Charles Darwin's eldest and most beloved daughter whose death from scarlet fever and tuberculosis at age $10$ in $1851$ devastated him and caused him to reject religious explanations of nature.

Galapagos Finches

A diverse group of closely related island finches whose beak forms evolved along distinct ecological trajectories to exploit specific food items, illustrating divergence from a common ancestor in isolation.

Alfred Russel Wallace

A British naturalist whose $1858$ manuscript describing natural selection prompted Darwin to co-author a joint paper and rapidly publish his own full thesis.

The Origin of Species (1859)

Charles Darwin's landmark $1859$ book detailing how any advantageous variation in an organism will tend to be preserved through the struggle for life and inherited by offspring via natural selection.

The Descent of Man (1871)

Darwin's $1871$ book extending evolutionary mechanisms to human origins, mental capacities, racial variation, and sexual dimorphism.

Monogenism

The view endorsed by Darwin that all human groups share a common single origin and lineage, framing human races as socially constructed rather than distinct biological species.

Angraecum sesquipedale

Darwin's Orchid from Madagascar, which features an extraordinarily long $30\text{ cm}$ nectary spur that led Darwin in $1862$ to predict the existence of a specialized long-tongued pollinator.

Xanthopan morganii praedicta

Morgan's sphinx moth from Madagascar, discovered in $1907$ and observed pollinating Angraecum sesquipedale in $1992$, confirming Darwin's coevolutionary prediction of a moth with an ultra-long proboscis.