Define Micro-evolution.
The gradual change in frequency of a gene within an organisms gene pool from generation to generation.
Define Macro-evolution.
The descent of different species from a common ancestor over many generations.
Name 7 scientific pieces of evidence for evolution.
Fossil records, Vestigial structures, Modification by descent (natural selection), Biogeography, Genetics, molecular biology, Comparative biochemistry and physiology, Comparative embryology.
When did life begin approx.?
3.6 Billion years ago.
What is radiometric age dating?
Dating the approximate age of fossils based on the decay of radioactive isotopes.
What is our current era? And current eon?
Cenozoic era, Phanerozoic eon.
What 3 periods consist of the Mesozoic era?
Triassic, Jurassic, Cretaceous.
Why can we make conclusions about evolution based on fossil records? Name 3 reasons.
Fossil records show; increase in complexity of organisms and life forms, increase in diversity, increase in size, from unicellular organisms in the water bodies to land mammals today.
Name two methods of dating rocks.
Radiometric age dating, Carbon-14-dating, molecular clocks, stratigraphy.
Modification by descent is based on the science of ______ structures.
Homologous structures.
What are homologous structures? Name two examples.
Structures within different organisms or species that are similar to that of a common ancestor. E.g. the genetic code, all organisms have same nucleotide bases, which make up their respective DNA and RNA. The pterodactyl limb which shares the same 3 main forearm bones — ulna, radius and humerus — with the human arm, frog arm and whale fin.
What are the 3 theories that support modification by descent?
Homologous structures (Divergent evolution), Analogous structures (Convergent evolution), Modification within a species (Natural Selection).
Who are four key role players in the proposition of the theory of evolution?
Erasmus Darwin, Jean Baptiste Lamarck, Alfred Russel Wallace, Charles Robert Darwin.
What did Erasmus Darwin famously propose?
Life has progressed in complexity, as if up a ladder from the first [unicellular] organisms to humans.
Explain Lamarckism.
Jean Baptiste Lamarck a French naturalist in 1801, proposed a theory of evolution that related to two key principles:
The Theory of Use and Disuse: the more an organisms used an organ, the larger it grew. Conversely, the less they used it the more small and less efficient it would become.
The Theory of Inherrance of Acquired Characteristics: these changes that an organism acquired throughout their life through use and disuse, would be passed onto their offspring — it is in this way populations would change and new species were then formed.
What were Darwin’s observations in the Galápagos?
Organisms of the same species produce many offspring, very few survive, survival depends on natural selection, or ‘selection of traits’ (or survival of the fittest).
What is Darwin’s gradualism?
Based on his observations in the Galápagos Islands that he based his theory of evolution on, Gradualism explains a very slow, gradual change in species over time.
Discuss Darwin’s theory of natural selection.
V - Genetic Variation in a population is present = certain organism with desirable traits to survive and thus reproduce more.
S - These organisms with “desired traits”, survive and reproduce more than those without them — those without desired traits die more often and reproduce less.
I - In reproducing, their offspring Inherit these desired characteristics.
T - Over evolutionary Time, this leads to new species being formed and significant changes within a population/ species.
How does artificial selection mimic natural selection?
Artificial selection aims to reproduce organisms with favorable characteristics, similar to how natural selection allows organisms with favorable traits to survive.
What is the process of adaptive radiation?
The rapid diversification of a common ancestor (or single species) into speciating into new species and occupying new ecological niches.
Such as in Darwin’s observations of the Finches on the Galapagos islands. These finches — who have descended from a common ancestor — rapidly evolved into significantly different species of finches over time to occupy different ecological niches (the functional role of an organisms within its environment, all the resources and conditions necessary for it to survive and reproduce).
What are some examples of microevolution in humans?
Examples include changes in skin color, lactose tolerance, and resistance to diseases.
What are the types of natural selection?
Natural selection, Genetic drift, Genetic flow.
Differentiate between convergent and divergent evolution.
Convergent evolution is when unrelated species evolve similar traits, while divergent evolution is when related species evolve different traits.
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Survivorship Curves & K-Strategists vs R-Strategists18
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Courtship & Reproductive Strategies To Ensure Repro. Success12
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Internal & External Fertlisation, & How Reproductive Success Is Ensured18
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The Pancreas & Diabetes32
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Reproductive Hormones - Endocrine System27
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Male & Female Reproductive System — Structures & Functions — Human Reproduction37
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The Menstrual Cycle — [Female] Human Reproduction.34
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Evolution Part 1 — Human Evolution34
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DNA, RNA & Protein Synthesis42
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Meiosis22
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Genetics & Genetic Engineering31
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Human Reproduction38
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Animal Reproductive Strategies26
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Endocrine — Systems, Processes & Functions36
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Flowering Plant Reproduction26
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Evolution Part 1 — Foundations & Evidence25
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Evolution Part 2 — Mechanisms, Selection & Speciation20
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Evolution Part 3 — Hominid Studies24
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PAT/ Practical Tips & Tricks — Excludes Exoerimental Design & Some Measurnment (Practice)19
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The Hominid Sequence - Evolution Part 341
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Population Ecology72
