Descent with Modification Flashcards
Evolution
descent with modification; can be viewed as both a pattern and a process
Scala Naturae
Organizes nature into a ladder of increasing value and complexity – developed by Aristotle
Why was Aristotles “scala naturae” well regarded within the 18th century?
It aligned with the Old Testament, where nothing evolved or changed. everything was made perfectly for their environments by God.
Catastrophism
–Each boundary between strata represents a catastrophe;
–changes in the earth’s crust during geological history have resulted chiefly from sudden violent and unusual events;
Who advocated for catastrophism?
Georges Cuvier
Jean Baptiste deLamarck (1744-1829)
speculated that species evolve through use/disuse of body parts, and the inheritance of acquired characteristics
Natural Selection
The cause of adaptive evolution - the process through which populations of living organisms adapt and change
Natural Selection impacts ___, while Evolution impacts ___:
Individuals; Populations
Observation of Nature #2: all species are capable of producing more ____ than the environment can support, but many of these fail to ____ and _____
offspring; survive & reproduce
Observation of Nature #1: members of a ____ often vary in their _____ traits.
population; inherited
Inference of Nature #1: Individuals whose _____ ____ give them a higher probability of _____ and _____ in a given environment tend to leave more _____.
inherited traits; survive & reproduce; offspring;
Inference of Nature #2: The (un/equal) ability of individuals to _____ and ______ will lead to the accumulation of ______ ______ in the population over generations
unequal; survive & reproduce; favorable traits;
Natural selection can only act on ____ ____.
Heritable Traits
Homology
similarity resulting from common ancestry
Homologous Structures
anatomical resemblances that represent variations on a structural theme present in a common ancestor
Analogous Structures
features of different species that are similar in function, but not necessarily in structure or ancestry, that developed in response to similar environmental challenges
What is a use of comparative embryology?
It can reveal anatomical homologies that aren’t visible in adult organisms, but are present at the embryotic stage.
Vestigal Structures
remnants of features that served important functions in the organisms ancestors
Convergent Evolution
the evolution of analogous features in distantly related groups, arising when groups independently adapt to environments in similar ways
Endemic
native and restricted to a certain place
