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Evolution - Coggle Diagram

- - - - Habitat Isolation: 2 species occupy different habitats within the same area
      - Temporal Isolation: 2 species mate at different times
      - Behavioral Isolation: 2 species differ in courtship rituals and so they do not attract each other
      - Mechanical Isolation: 2 species attempt to mate by morphological differences prevent sucessful completion
      - Gametic Isolation: sperm of one species cannot fertilize the eggs of another species
    - - Reduced Hybrid Viability: genes of different parent species may impair hybrids development or survival
      - Reduced Hybrid Fertility: genes of different parents may impede hybrids ability to produce normal gametes
      - Hybrid Breakdown: first generation may be healthy and fertile but second generation and so forth become less healthy and/or fertile
  - - - Biological Species Concept: species are separated by reproductive barriers (applies to sexual species)
      - Morphological Species Concept: species are separated by body shape and other structural features
      - Ecological Species Concept: determines species by ecological niche (how the organism interacts with the environment)
    - - Allopatric Speciation: gene flow is interrupted when population is divided geographically
      - Sympatric Speciation: speciation occurs between population that lives within the same area
        
        polyploidy: extra set of chromosomes due to accident during cell division
        
        auto polyploidy: individual that has more than 2 chromosomes sets derived from a single species
        
        allopolyploids: a fertile hybrid that has more than 2 chromosomes sets due to interbreeding between 2 species
        
        sexual selection: mate choice by females can result in a reproductive barrier and lead to species divergence
        
        habitat differentiation: subpopulation exploits a habitat or resource not used by parent population
- - - - Hadean Eon started: 4.5 BYA ended: 4 BYA
        
        Early formation of Earth characterized by extreme heat and volcanic activity, living organisms did not exist at this time
      - Proterozoic Eon started: 4 BYA ended: 2.5 BYA
        
        First single celled prokaryote is thought to exist in this eon about 3.5 BYA in the ocean
        
        Formation of the Earth's Crust which led to the first continental land masses
        
        Development of Oceans where life was first formed
      - Proterozoic Eon started: 2.5 BYA ended: 541 MYA
        
        We also see the transition to an oxygenated environment in this eon known as the " Oxygen Revolution"
        
        Emergence of important geological processes including plate tectonics
        
        First Eukaryotes are formed 1.8 BYA due to endosymbiosis
        
        endosymbiosis: when a prokaryotic cell engulfs a small cell that would evolve into an organelle found in all eukaryotes: the mitochondria
        
        Early Multicellular Eukaryotes are formed 1.3 BYA
        
        Edicardian Era: 635 MYA-541 MYA
        
        The emergence of larger and more diverse multicellular eukaryotes
        
        soft bodied organisms including both algae and animals
        
        set the stage for Cambrian explosion
      - Phanerozoic Era started: 541 MYA ended: present day
        
        Paleozoic Era: 541-252 MYA
        
        Cambrian Explosion: many present-day phyla seemed to evolve into what they are today in the Cambrian period
        
        animals appear to develop claws and other features for hunting prey and simultaneously new defensive adaptations arise
        
        Colonization of land begins on a larger scale than before around 500 MYA, mostly plants and arthropods (first animals to colonize land)
        
        supercontinenets begin to form
        
        era ended with mass Permian extinction event
        
        Mesozoic Era started: 252 MYA ended: 66 MYA
        
        Emergence of dinosaurs and first mammals
        
        Pangea is formed and splits apart during this Era
        
        Appearance of the first birds
        
        Climate was generally warmer until the mass extinction event which killed the dinosaurs
        
        Meteor hits Earth and causes a fog in the atmosphere consequently lowering temperatures and killing off the dinosaurs leading to the era of mammals
        
        Cenozoic Era started: 66 MYA ended: ongoing
        
        Mammalian evolution
        
        Major Ice age
        
        rise of early homonids (humans)
        
        modern day humans emerged approx 300,000 YA
    - - Permain Extinction: occured due to mass volcanic eruptions that wiped out a majority of life in the ocean
      - Cretaceous Extinction: occurred due to a large meteorite crashing into Earth and causing a dust cloud to surround the atmosphere lowering temperatures and leading the extinction of half of marine species as well as dinosaurs
  - - - Fossil Record is largely incomplete due to the specific requirements for making a fossil
        
        had hard shells/skeletons or other parts that facilitated in fossilization
        
        favors species that were widespread in certain enviornments
        
        favors species that lived a very long time
    - - Radiometric Dating: based on decay of radioactive isotopes
      - rate of decay is expressed by half-life: the time required for 50% of the parent isotope to decay
      - Fossils contain isotopes of elements that are accumulated in the organisms when they were alive
      - most common element isotope in living organisms is carbon (carbon dating works for fossils up to 75000 years ago)
  - - - The abiotic synthesis of small organic molecules, such as amino acids and nitrogenous bases
        
        Oparin and Haldane hypothesize that Earths early atmosphere was reducing in which organic compounds could have formed from simpler molecules due to lighting or UV radiation.
        "Primitive soup theory"
        
        Miller and Urey tested Oparin/Haldane theory and yielded amino acids in the hypothesized conditions of early Earth
      - The joining of these small molecules in macromolecules such as proteins and nucleic acids
      - The packaging of these molecules into protocells
        
        protocell: self-organized, endogenously ordered, spherical collection of lipids proposed as a rudimentary precursor to cells
      - The origin of self-replicating molecules that eventually made inheritance possible