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A Reptile That Escaped Extinction.

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Greetings. The Blue Iguana is a reptile native to the island of Grand Cayman. Once critically endangered, the species numbered only 15 wild individuals in 2003, but thanks to the herculean efforts of conservationists, the species' population has rebounded to a more healthy and sustainable status.  A herbivorous reptile, Cyclura lewisi feeds on plants, fruits, and flowers. Adults have no natural enemies, with the only threat posed by human activities like habitat destruction. Young blue iguanas are occasionally preyed on by cats and dogs brought to the island by settlers. Blue iguanas are a prime example of island gigantism, being totally isolated on the island for the past tens of thousands of years, allowing for the species' substantially larger body dimensions. Adults reach lengths of 1.8 meters with weights of 16 kilograms commonly reported. Blue iguanas prefer rocky habitats, open, sunny, and free of forested areas. Armed with powerful limbs and clawed digits, the animals ...
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35%. An Arthropod's Atmospheric Garden Spot.

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Greetings. The Carboniferous Period lasted from about 359.2 to 299 million years ago. During the Carboniferous, atmospheric oxygen levels attained a peak of around 35%, significantly higher than the current 21% oxygen level, with this high concentration occurring towards the end of the Carboniferous, approximately 300 million years ago.  The high oxygen levels during the Carboniferous were largely the direct result of the vast planetwide growth of swamp forests which absorbed copious amounts of atmospheric carbon dioxide, releasing a surplus of oxygen into the atmosphere. The high oxygen levels contributed to the large size of insects and other arthropods during this period, as higher oxygen levels facilitate larger body dimensions.  In addition to having the ideal conditions for the formation of coal, several major biological, geological, and climatic events occurred during this time. One of the greatest evolutionary innovations in the history of complex life on the planet oc...
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Everett Olson and His Contribution to the Mass Extinction Narrative.

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Greetings. Olson's Extinction, named after paleontologist Everett C. Olson, was a mass extinction that occurred approximately 273 million years ago during the Late Permian period. The extinction predated the monumental Permian/Triassic extinction event by a few million years.  Olson first identified a substantial gap in fossil record strongly indicating an abrupt change between the early Permian and middle/late Permian faunas. This event has been argued by many paleontologists to have affected many taxa, including embryophytes, marine metazoans, and tetrapods. The first signs that indicated extinction came to light when Olson noted a hiatus between early Permian faunas dominated by pelycosaurs and the therapsid-dominated faunas of the middle and late Permian. Initially taken to be a preservational gap in the fossil record, the event was originally dubbed "Olson's Gap." To compound the difficulty in identifying the cause of the "gap," paleontologists had diff...
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