Topic 5: Evidence for Evolution Flashcards

Vocabulary practice flashcards covering key evidence for evolution, including direct observation, homologies, the fossil record, and biogeography.

Homologies

Similarities among different organisms that arise from a shared evolutionary ancestor.

Morphological Homologies

Physical resemblances representing variations on a structural theme present in a common ancestor, such as the mammalian forelimb structure.

Embryonic Homologies

Conserved anatomical features during early developmental stages in vertebrates, such as pharyngeal pouches and post-anal tails in chick and human embryos.

Vestigial Structures

Remnants of anatomical features that were functional in an organism's ancestors but no longer serve their original function, such as the pelvic and femur bones in whales.

Molecular Homologies

Shared biological traits at the genetic level, including a universal genetic code used to translate RNA into proteins, and shared gene or protein sequences.

Industrial Melanism

An evolutionary process where dark-coloured variants of a population increase in frequency due to selective predation, as observed in the peppered moth (Biston betularia) during the Industrial Revolution.

Artificial Selection

Human-driven selective breeding in domesticated animals and plants for specific phenotypic traits over generations, such as milk yield in cows or egg production in hens.

Methicillin-Resistant Staphylococcus aureus (MRSA)

A dangerous bacterial pathogen that evolved resistance to penicillin in 1945 and methicillin in 1961 shortly after the drugs were introduced.

Fossil Record

The historical sequence of life preserved in sedimentary rock strata that provides a timeline of species origins, extinctions, and gradual evolutionary transformations.

Transitional Fossils

Fossils that document intermediate forms in ancestral lineages leading to modern species, illustrating major evolutionary transitions such as land mammals evolving into cetaceans.

Biogeography

The study of the geographic distribution of living organisms and fossils through space and time, shaped by geological history, continental drift, and dispersal.

Pangaea

A single Earth supercontinent formed approximately 250 million years ago that subsequently fragmented through continental drift.

Endemic Species

Species that are native to a specific geographic region and are not naturally found anywhere else in the world.

Galápagos Finches

A group of 18 bird species that descended from a South American ancestor approximately 2 to 3 million years ago and diversified across islands in beak morphology to fill distinct ecological niches.

Hawaiian Honeycreepers

A group of approximately 50 to 60 species, including the scarlet honeycreeper (Drepanis coccinea), that descended from a single colonizing species around 7 to 8 million years ago.