lesson 1

evolution

change in gene freq in populations over time; any change in the heritable traits within a population across generations

evolvere

evolution came from the latin word ___ which means to unfold or unroll

nothing in biology makes sense except in the light of evolution

unifying concept in biology

Theodosius Dobzhansky

he stated that “nothing in biology makes sense except in the light of evolution”

Anaximander

6th century BC; Greek philosopher who proposed that life arose in water and simpler forms of life preceded more complex forms

plato

3rd century BC; greek philosopher who introduced that concept of essentialism

essentialism

centered on the concept of eidos, the form or idea imperfectly represented on earth such that what we see are simply imperfections of the essence of the being

Aristotle

3rd century BC; greek philosopher who developed the great chain of being or scala naturae

great chain of being

follows a hierarchical structure of all matter and life as decreed by god or a higher being; special creation

special creation

each species was created by god in the same form it has today and order is superior to disorder, so god’s creation must follow a plan of gradation from inanimate objects to barely animate forms of life, and finally to man who is both physical and spiritual in nature

Carl von Linne

18th century AD; swedish naturalist who wrote systema naturae

relatedness

meant proximity in the creator’s design

Georges-Louis leclerc, comte de buffon

18th century AD; french naturalist who predicted that the earth is more than 6000 years old based on the cooling rate of iron

Georges-Louis leclerc, comte de buffon

introduced the idea that species distinctions should be made on the basis of whether there were reproductive barriers to crossbreeding between groups; father of biogeography

georges cuvier

19th century AD; french naturalist and zoologist who established extinction as fact based on fossil remains

Georges cuvier

founder of paleontology; diff fossils on diff layers or strata

james ussher

irish archbishop of armagh & primate of all ireland; time & death of crration at 6pm on 22 october 4004 bc

Jean baptiste lamarck

french naturalist who proposed the inheritance of acquire characteristics and transformational theory

use and disuse

by using or not using its body parts, an individual develops certain characteristics that it can pass on to its offspring

charles lyell and james hutton

british geologists; proponents of uniformitarianism

uniformitarianism

• The Earth changed gradually through the same

processes operating in the past as in the present

Alfred Russel Wallace and Charles Darwin

british naturalists •Proposed evolution by natural selection

faunal divide (Wallace Line)

separates the Indonesian Archipelago

into those of the Asian and

Australasian origin

hms beagle

charles darwin wrote on the origin of the species by means of natural selection based on his travels on the

natural selection

indiv with inherited characteristics that make them fit in their envi are most likely to survive and reproduce, leave more offspring than less fit indiv

Artificial selection

Genetic variation maintained by natural selection

MICROEVOLUTION (below the species level)

1. Fossil record

   2. Comparative anatomy

   3. Anatomical ad hoc modifications

   4. Comparative embryology

   5. Molecular biology

MACROEVOLUTION (at or above the species level)

Artificial selection

•Plant and animal breeding led to the emergence of

various crop plants and different breeds of farm animals

Artificial selection

breeder rather than nature; allows us to see selection and evolution in real time

sicle cell anemia

British peppered moth Biston betularia

genetic variation maintained by natural selection examples

fossil record

archaeopteryx, tiktaalik roseae

comparative anatomy

analogous vs homologous, vestigial

HOMOLOGOUS STRUCTURES

•Structures with the same embryonic origin

ANALOGOUS STRUCTURES

•Structures that resemble each other physically or

functionally but do not have the same embryonic origin

vestigial organs

Organs that arise because an organism adapting to a

new environment usually carries along some previously

evolved structures that are no longer necessary

appendix

found in the digestive tracts of many extant herbivores; houses mutualistic bacteria which help animals digest the cellulose molecules that are found in plants

human appendix

may harbour and protect bacteria that are beneficial in the function of the human colon

oswald avery

identified dna as genetic material

ronald fisher
john bs haldane
sewall wright

popn genetics mutations as the raw material for selection

sergei chetverikov
theodosius dobzhansky

study of genetic variation, genetics and origin of species

ernst mayr
bernhard rensh
g. ledyard stebbins
george gaylord simpson

pioneer microevolution and macroevolution

alexander oparin, john burdon haldane

organic molecules; independently proposed that early earth atmospheres

james watson francis crick rosalind franklin

molecular evolution

stanley miller
harold urey

tested oparin and haldane’s proposal by creating set up at lab; postulated proof that building blocks of life could be synthesized abiotically from gases

motoo kimura

neutral theory of evolution

anatomical ad hoc modifications

comprises in anatomical structures as a result of post hoc modifications

• 'back to the drawing board' is not an option

• result in 'imperfections' in the design

comparative embryology

•Closely related organisms have similar stages in their

embryonic development

Molecular biology

•Related individuals have greater similarity in their DNA

and proteins than do unrelated individuals

Frederick Sanger and colleagues (1955)

First comparison of amino acid sequences (INSULIN)

from different species

biogeography

island endemism, continental drift of fossil distribution

neutral theory of evolution

by chance not by natural selection; degeneracy of the genetic code

louis pasteur

his experiments disproved abiogenesis-spontaneous generation