The five major extinctions by andrew hantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77 en-us 2021-06-04 18:55:43 UTC 2025-10-26 04:33:51 UTC hello@padlet.com The Ordovician-Silurian Extinction andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586076626 The Ordovician-Silurian Extinction was the first major extinction and took place around 440 million years ago. It was characterized by sea levels rising and lowering rapidly due to glaciation and interglacials capturing water and releasing it over and over again. This killed around 49 to 60 percent of all marine life, which was the majority of what life was then. This forced life to evolve to live on land.

(Image is fossil trilobites from the Ordovician age)]]> 2021-06-04 18:57:45 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586076626 andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586092372 2021-06-04 19:06:39 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586092372 The Devonian Extinction andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586096654 The Devonian Extinction was the second major event and was the second biggest extinction event. It took place around 365 million years ago, and killed nearly 80 percent of all living things. The first wave was believed to have been caused by lack of oxygen in the oceans, due to so many organisms adapting to live on land, and the second wave was the major decrease in greenhouse gasses causing temperatures to rapidly drop. But the third wave is really unknown. Our best guess is meteor strikes or volcanic activity, but we really don't know.

(Image is limestone full of bryozoa, crinoid, and brachiopod fossils from the Devonian period)]]> 2021-06-04 19:08:51 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586096654 andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586111413 2021-06-04 19:16:20 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586111413 The Permian-Triassic Extinction andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586115418 The Permian-Triassic Extinction was the third extinction event, occurred about 250 million years ago and was easily the biggest extinction event at an astronomical 96 percent of all living things going extinct. It is referred to as "The Great Dying" due to how many species died. It was so large that it rocketed time out of the Paleozoic era and into the Mesozoic era. And the crazy thing is that we don’t even know what caused it. Our best guess was a combination of volcanic activity, as well as meteors putting methane and basalt into the air, suffocating nearly every living thing.

(Image is of a Dimetrodon, which went extinct in The Great Dying)
]]> 2021-06-04 19:18:34 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586115418 andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586124088 2021-06-04 19:23:18 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586124088 The Triassic-Jurassic Extinction andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586126600 The Triassic-Jurassic Extinction is the fourth and most boring extinction event. Taking place 210 million years ago, this extinction event killed nearly 50 percent of all living species. It really isn't an extinction event at all, though. It's more of a combination of many minor extinction events that happened over the past 18 million years. It did really begin the rise of dinosaurs, though, as shown in the image below.]]> 2021-06-04 19:24:50 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586126600 andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586137559 2021-06-04 19:31:02 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586137559 The Cretaceous-Tertiary Extinction andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586138471 The Cretaceous-Tertiary Extinction is the one you're probably most familiar with. Maybe not by name but definitely by what went extinct at the time; The Dinosaurs. The most recent of the extinction events, at around 65 million years ago, also is one of the most unknown ones as well. Racking in at around 75 percent of all species dying, The Cretaceous-Tertiary Extinction causes a lot of controversy on how it happened. Some say it was the high volcanic activity, some say it was a meteor shower. I, personally, think it was a combination of both, much like The Permian-Triassic Extinction. The meteors and volcanoes made the air thick with methane and suffocated every living being on the planet.

(Image is of a "modern" dinosaur, whos skeleton is placed in a museum as an artifact of time)]]> 2021-06-04 19:31:30 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586138471 andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586148531 2021-06-04 19:37:47 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586148531 Vocabulary andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586151686
  • VIST: Variation, Acquisition of genes, Selection, and Time
  • Natural Selection: Certain traits and genes making it easier to survive
  • Mutation: A change in DNA that may be passed to other generations
  • Sexual Selection: The theory that evolutionary traits can be solved by competition
  • Genetic Drift: The change in the frequency of genes
  • Bottle Neck Effect: The sudden decrease and significance of a species' population
  • Founder Effect: Smaller genetic diversity from a small number of colonizing ancestors
  • Homologous Structures: Same ancestor, different function, similar structure
  • Vestigial Organs: "Useless" organs that our ancestors once used, but we don't need anymore
  • Ontogeny Recapitulates Phylogeny: The hypothesis that an organism will replicate it's ancestors
  • Molecular Evolution: The study of evolutionary change at the level of the DNA sequence
    • ]]>     2021-06-04 19:39:46 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586151686     The Five Major Extinctions andrewhantzmon https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586152485 Andrew Hantzmon, period 3 Biology]]> 2021-06-04 19:40:15 UTC https://padlet.com/andrewhantzmon/tcr28q8l7vvt9p77/wish/1586152485