Biology Module 3: Biological Diversity

Flashcards covering the evidence for evolution, technologies for gathering evidence, the Darwin-Wallace theory, models of evolutionary pace, and types of adaptations.

Biodiversity

The variety of living things which live in a particular place, ecosystem, or on the entire Earth, with estimates ranging from $1 \text{ million}$ to over $30 \text{ million}$ types.

Palaeontology

The study of fossils which acts as the most important direct evidence showing that life on Earth has changed in a sequence over time.

Radiometric Dating

A technology used to determine the actual age of rocks and fossils by measuring the residual radioactivity of naturally-occurring radio-isotopes.

Transitional Forms

Fossils that provide evidence of one type of life evolving into another by showing intermediate features, such as the dinosaur-bird Archaeopteryx.

Biogeography

The study of how life is distributed geographically, which provides evidence for evolution through the observation of unique species evolving on isolated continents.

Comparative Embryology

The comparison of vertebrate embryos during development to identify similarities, such as gill arches and tails, that suggest a common ancestor.

Comparative Anatomy

The study of body structures across different organisms to identify shared features that imply common ancestry, such as the Pentadactyl Limb.

Pentadactyl Limb

An ancestral bone structure consisting of $1 \text{ bone}$ in the upper arm, $2 \text{ bones}$ in the forearm, and $5 \text{ sets}$ of finger bones, shared by various vertebrates.

Biochemistry

The study of molecular similarities, such as the identical genetic code in DNA and enzymes used for respiration, which indicates that all life evolved from common ancestors.

Selective Breeding

The process by which humans deliberately choose individuals with specific traits to breed, proving that a species can be significantly changed over generations.

Isotopes

Atoms of the same chemical element that have the same number of protons and electrons but a different number of neutrons.

Radio-isotopes

Unstable isotopes that are radioactive and decay at a predictable rate over time.

Half-life

The constant amount of time it takes for the level of radiation in a radio-isotope to drop to half of its previous level.

Carbon-14 Dating

A radiometric dating method used for human history artifacts, utilizing an isotope with a half-life of approximately $5,700 \text{ years}$.

Natural Selection

A cornerstone of the Darwin-Wallace theory describing how environmental factors select which individuals survive and breed based on their suitability to conditions.

Survival of the Fittest

The principle that individuals with characteristics best suited to their environment are the ones most likely to survive and pass on their traits to offspring.

Variation

The differences among individuals within a species, which is essential for survival when environmental changes occur.

Divergent Evolution

The process by which isolated populations of a single species evolve along different paths, eventually forming multiple new species.

Speciation

The formation of new species, which relies heavily on the isolation of populations to prevent interbreeding.

Convergent Evolution

The process where unrelated organisms evolve similar features because they live in similar environments, such as the streamlined bodies of sharks and dolphins.

Micro-evolution

Small evolutionary changes in a population's genetic shift over generations, such as antibiotic resistance in bacteria or the shift in English Pepper Moth colors.

Olympic Village Effect

A phenomenon observed in cane toads where individuals at the front of an invasion evolve larger bodies and longer legs to move faster, reaching rates over $30 \text{ km}$ per year.

Gradualism

A model of evolution where new species form through a slow, steady accumulation of small changes over millions of years.

Punctuated Equilibrium

An evolutionary model proposing that species remain stable for long periods, followed by rapid bursts of change in response to dramatic environmental shifts.

Monotremes

An ancient group of mammals, including the platypus, that are warm-blooded and have fur but lay eggs like reptiles.

Structural Adaptations

Physical features of an organism's body structure that aid survival, such as the thick fur of a bear or the water-storing tissues of a cactus.

Physiological Adaptations

Specialized internal functions of the body that help a plant or animal survive, such as kidneys that produce concentrated urine to conserve water.

Behavioural Adaptations

Inherited, instinctive actions taken by animals to help them survive, such as a blue tongue lizard sunbaking to increase body heat.

Biotic Factors

The living components of an environment that affect a species, including food sources, predators, diseases, and competitors.

Abiotic Factors

The non-living physical and chemical components of an environment, such as light intensity, temperature range, and water availability.

Biological Control

The use of one living species to control the population of a pest species, such as the introduction of the cactoblastis moth to manage Prickly Pear.