History of evolution Flashcards
What is evolution ?
The change in the gene pool from generation to generation due to natural selection, gene mutation and genetic drift.
What did Georges Cuvier note in early 1800’s ?
That different forms of life existed at different layers of the earth.
Extinction
What did Jean-Baptiste Lamarck propose in the early 1800’s?
The use/disuse theory
What is the use/disuse theory ?
That the more organs/ traits are used, they grow stronger.
The less they are used, the less present they are (can completely disappear after a while).
Those traits are passed on to children
What did James Hutton believe (early 1800’s)?
That gradual natural forces (such as wind) influence the development of the planet.
What did Charles Lyell propose ?
Uniformitarianism
What is uniformitarianism ?
A theory that proposes that life and the planet are influenced by consistent natural forces throughout time.
What did Thomas Malthus propose in 1798 ?
The challenges between population growth and limited ressources Malthusian Catastrophe (if ressources are unsufficient)
What did Alfred Wallace and Darwin discover ?
Natural selection
Darwin indicated that life had what ?
Unity
Diversity
Adaptation to make organism fit to a specific environment
What is natural selection ?
The fact that the species with the most adapted characteristics/traits have greater odds of survival and reproduction.
What did Miller and Urey recreated in 1953? ?
They succesfully recreated over 30 amino acids out of simple molecules and an electrical spark.
What are the steps of abiogenesis ?
Formation of biomolecules
Formation of polymers
Formation of a membrane
The ability to self-replicate (ex: ribozymes)
What is abiogenesis ?
The process of forming life from a non-biological source
What two organelles of the eukaryotic cell are thought to be originally prokaryotic cells ?
Mitochondria
Chloroplast
The first life-forms are thought to be autotrophs or heterotrophs ?
Heterotrophs
What are phototrophs ?
Organisms that produce (and use) oxygen (such as plants)
Did plants or animals live first on land ?
Plants, which produced the oxygen allowing further biodiversity to develop.
What adaptations did plants that live on land have to undergo ?
Stonger stuctural support (because of gravity)
Have more vascular tissue (to carry nutrients easier)
Avoid water loss (evaporation, or from other animasl)
Need effective method to disperse seeds
What kind of heterotrophs are animals ?
Heterotrophs by ingestion
Animals are the only branch of life that display what tissues ?
Nervous tissue
Muscle tissue
What is bilateral symmetry ?
Having a single axis of symmetry
What is radial symmetry ?
Having multiple plains of symmetry
What is cephalization ?
The formation of an area with a large concentration of nervous tissue (e.i. brain)
What is segmentation ?
The division of the body into sections (allows differentiation of different tissues)
How can evolution be observed ?
Fossils and Radiometry Continental drift and biogeography Anatomy and physiology Molecular evidence Present exampes of evolution
What is biogeography ?
The distribution of living organisms on the planet correlated to their geography
What is convergence ?
When organisms not directly related through ancestors adopt simlar characteristics
What is divergence ?
When organisms sharing a common ancestor change in different ways at one point (which leads to speciation)
What is a vestigial structure ?
A structure that is no longer used for its primary purpose
What concepts define what a species is ?
Biological species concept
Morphospecies concept
Ecological species concept
Phylogenetic species concept
What is macroevolution ?
Large-scale changes in organisms with different physical traits
What is microevaluation ?
Slight changes in allele frequency from one generation to another (caused by DNA mutations)
