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Evolution - Coggle Diagram

- - - - Traveled on HMS Beagle (1831–1836).
        
        Voyage to chart stretches of the South American coast/Research gathered here greatly supported his writings
        
        he noted that finch species varied from island to island, Reasoning for birds being named "Darwin's Finches
        
        Studied finches, tortoises, and other species in the Galápagos Islands
        
        He described features of organisms that made them well suited to such diverse environments
      - Born in 1809, died in 1882.
        
        Married his cousin
      - Influences
        
        Studied under botanist John Stevens Henslow, at Cambridge University
        
        Thomas Malthus
        
        an economist, ideas on population growth and competition influenced Darwin’s
        understanding of survival
        
        James Hutton and Charles Lyell
        
        proposed the principles of gradualism and uniformitarianism, which
        influenced Darwin's understanding of Earth's age
        
        Georges Cuvier
        
        introduced paleontology and supported catastrophism but rejected the idea of evolution
        
        Aristotle
        
        proposed the idea of the Scala of Naturae, suggesting a hierarchy of life forms, each perfectly
        created by god and growing in complexity
        
        Jean-Baptiste Lamarck
        
        suggested mechanisms like "use and disuse" and "inheritance of acquired
        characteristics," though later disproven
      - Made groundbreaking discoveries with his theories of natural selection and evolution was a departure from prevailing views
        
        His work laid the foundation for modern evolutionary biology
    - - Darwin published several works
        
        In 1884 he wrote his ideas but was reluctant to publish them due to controversy, he knew they would challenge the world/ He refined his theory for many years
        
        Alfred Russel Wallace
        
        independently conceived the theory of Natural Selection/This urged Darwin to publish his
        
        The Origin of Species (1859)
        
        Key Concepts Introduced and Inferences that were created from his Concepts
        
        Variation
        
        Individuals within a species show differences in traits
        
        Natural Selection
        
        The process by which individuals with traits better suited to their environment survive and reproduce more successfully
        
        Descent With modification/Evolution
        
        Over generations, species change and give rise to new species, all sharing a common ancestor.
        
        Over Production
        
        Organisms produce more offspring than the environment can support.
        
        Adaptations
        
        inherited characteristics of organisms that enhance their survival and reproduction in specific environments
        
        Darwin succeeded where previous evolutionists had failed
      - Evidence that supports Darwin's Ideas/Researchers have directly observed natural selection leading to evolution in many studies in diverse organisms
        
        Natural Selection with Invasive Species
        
        Soapberry bugs evolved shorter beaks through natural selection to better feed on a new plant, showing adaptation in response to environmental change.
        
        Endemic species are found only in specific locations.
        
        Homology
        
        shows that related species share traits from a common ancestor, even if those traits serve different functions today
        
        Fossil Records
        
        shows gradual changes in species over time, supporting evolution through examples like reduced pelvic bones in sticklebacks and whale ancestry.
        
        The study of fossils to understand life’s history is called Paleontology
        
        Biogeography
        
        supports evolution by showing how species' locations match patterns predicted by continental drift and common ancestry.
        
        Convergent evolution
        
        Distantly related species can develop similar traits due to similar environmental pressures
- - - - Differences in DNA sequences among individuals in a population, which often lead to differences in traits.
        
        EX of Variations
        
        Phenotypic Variation
        
        Observable differences in traits like height, voice, or coat color.
        
        Genetic Variation
        
        Variation in traits often reflects underlying genetic differences.
        
        mechanisms that alter allele frequencies
        
        Natural Selection
        
        process by which individuals with traits better suited to their environment tend to survive and reproduce more successfully
        
        Genetic Drift
        
        Genetic drift is the random change in allele frequencies from one generation to the next, especially in small populations.
        
        Founder effect
        
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        The Bottleneck Effect
        
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        Gene Flow
        
        the transfer of alleles into or out of a population due to the movement of fertile individuals or their gametes
      - Natural Selection Further Explained
        
        Types of Natural Selection
        
        Relative Fitness
        
        how well an individual’s traits help it survive and reproduce compared to others in the population.
        
        Directional
        
        conditions favor individuals exhibiting one extreme of a phenotypic range
        
        Disruptive
        
        conditions favor individuals at both extremes of a phenotypic range
        
        Stabilizing Selection
        
        against both extreme phenotypes and favors intermediate variants.
        
        Natural selection drives adaptive evolution by favoring traits that increase an organism’s chances of survival and reproduction in a specific environment.
    - - Formation of New Alleles
        
        New alleles arise through mutations—changes in DNA sequence—which can be caused by replication errors, radiation
      - Altering Gene Number or Position
        
        Gene duplications and chromosomal rearrangements can create new genetic material, sometimes leading to beneficial traits or new gene functions over generations.
      - Rapid Reproduction
        
        prokaryotes have many more generations per unit of time, so mutations can quickly generate genetic variation in their populations.
      - Sexual Reproduction
        
        genetic variation in a population results from the unique combination of alleles that each individual receives from its parents
        
        crossing over
        
        independent assortment
        
        fertilization
    - - mathematical formula that predicts how gene frequencies will remain constant from generation to generation in a population that is not evolving:
        
        Allele Frequency Formula
        
        p+q=1
        
        p = frequency of the dominant allele
        
        q = frequency of the recessive allele
        
        Genotype Frequency Formula
        
        P2 + 2pq + q2 = 1
        
        p² = frequency of homozygous dominant genotype (AA)
        
        2pq = frequency of heterozygous genotype (Aa)
        
        q² = frequency of homozygous recessive genotype (aa)
        
        population that is not evolving
        
        Hardy-Weinberg Equilibrium
        
        Conditions for Hardy-Weinberg Equilibrium
        
        No mutations – The gene pool must not be altered by mutations.
        
        Random mating – Individuals must pair by chance, not according to their genotypes or phenotypes.
        
        No natural selection – All individuals must have equal chances of survival and reproduction.
        
        Extremely large population size – To prevent genetic drift from affecting allele frequencies.
        
        No gene flow – No migration of individuals into or out of the population.
      - Gene Pool
        
        population’s genetic makeup