The Ordovician Period

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The Paleozoic era was some place around 542 million years back to 251 million years prior, otherwise called the timeframe when the supercontinent, Pangea, was still around. The Paleozoic time started with the Cambrian Period (lasted 53 million years). Amid this period there was the "Cambrian explosion" which introduced the Earth to arthropods (considered the ancestors of today's insects and crustaceans) and chordates (animals that have a notochord). This evolution created the colonization of the first creatures with vertebrates to walk among the Earth. After the Cambrian Period came the Ordovician Period (lasted 45 million years). This time period was marked in the fossil record by an abundance of marine invertebrates (spineless creatures). After the Ordovician Period came the Silurian Period (443 million years ago to 416 million years ago), which saw the spread of jawless fish all through the oceans. …show more content…

This was the time when plants evolved, however they in all probability did not yet have leaves or the vascular tissue that is present in today's plants to siphon up water and supplements, this evolution made its appearance during the Devonian period of the Paleozoic era. According to http://www.livescience.com/37584-paleozoic-era.html, “The Devonian Period saw the rise of the first land-living arthropods, including the earliest ancestors of spiders.” Following the Devonian period, came the Carboniferous period, which was somewhere around 359-299 million years ago. The fish population increased in diversity as the Trilobite population began to decline. Dragonflies also became more common during this

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