The Tertiary period began...
The Pliocene epoch began...
What does interspecific mean?
That the variation between 2 samples is due to the fact that they are from different species (and can not reproduce)
What is punctuated equilibrium?
The theory that rapid change takes place in a short period of time, often due to a speciation event/mutation that led one variation to be so beneficial that the other did not survive
This change is both preceded and followed by long periods of stasis
What did John Ray do?
Classified plants using observable data (empirical approach)
Came up with the concept of "species"
What is an incipient species?
The beginning of a new species (a group that is about to become a seperate species from other related individuals)
What is phyletic gradualism?
This is the theory that small changes accumulate in lineages over long periods of time, resulting in a slow but steady divergence and eventual speciation
Also called "Darwinian Evolution"
What is the goal of classifying organisms?
To reflect evolutionary relationships (phylogeny)
The first vertebrates appeared...
500 mya during the Paleozoic era
The Quaternary period consists of what epochs?
Holocene and Pleistocene
What is homoplasy?
The term that describes analogous features (also called characters); developed by different groups of organisms independently and not through shared ancestry.
"Father of Taxonomy"
The Holocene epoch began...
.01 mya (10,000 years)
The Paleocene epoch began...
The Pleistocene epoch began...
The Eocene epoch began...
Describe Linnaeus' system of taxonomy
A hierarchical system that classifies organisms into inclusive categories, from most inclusive to least inclusive
Describe parapatric speciation
When 2 populations have overlapping geographic ranges, resulting in only partial reproductive isolation
The geographic ranges are different enough that they result in selection for different variations, and seperate enough that gene flow is reduced (increasing variation between the populations)
The interbreeding between the 2 populations results in an incipient species
The Miocene epoch began...
Describe sympatric speciation
There is no geographic or reproductive isolation, but some niche causes a reduction in gene flow and results in random speciation
More theoretical than empirical
The Oligocene epoch began...
The science of naming and classifying
What is the biological species concept?
The idea that a species is a group of actually or potentially interbreeding individuals who are reproductively isolated from other groups
i.e. only members of the same species can produce fertile offspring
What are the important factors in determining a fossil species?
Deciding if variation is interspecific or intraspecific
Comparing to modern reference samples
Dealing with the problem of time (tempo of speciation and not knowing time frame)
What are the 3 modes of speciation?
When does speciation occur?
When a group splits and becomes so isolated from each other that they are no longer able to reproduce
The first placental mammals appeared...
70 mya during the Mesozoic era (reptiles were the dominant land vertebrates)
The Cenozoic era consists of what periods?
Quaternary and Tertiary
What is the purpose of reconstructing phylogeny and how is it done?
The purpose is to find out what the evolutionary relationships are
It is done by identifying homologous traits (homologies) and analogous traits (analogies)
When naming an organism at the species level, you must also include the...