The first evolved during the orbovician period

Amid the Ordovician Period, the outside of the earth was drastically unique in relation to it is today. About all life on earth was in the seas. The main land life was as exceptionally crude plants extremely close to the water line of the coasts, presumably greeneries and green growth and were of a non-vascular nature.  

The Ordovician Period started with a noteworthy eradication called the Cambrian– Ordovician annihilation occasion, about 485.4 Mya (million years prior). It went on for around 42 million years and finished with the Ordovician– Silurian elimination occasions, about 443.8 Mya (ICS, 2004) which cleared out 60% of marine genera.  

The timeframe that occurred 488 to 443 million years back. Amid the Ordovician time frame, some portion of the Paleozoic time, a rich assortment of marine life thrived in the tremendous oceans and the primary crude plants started to show up ashore—before the second biggest mass annihilation ever finished the period.

Fish first emerged during the Ordovician season which originated around 530 million ages ago. It was during a particular time when the ancient chordates originated to acquire the skull and the vertebral column. The type of fish that first appeared was jawless and small known as conodonts and it was an invertebrate. The first vertebrate was also a fish that was jawed and it probably appeared late in the Ordovician period which was represented in the fossil record.

name and explain one of the event that occurs during meiosis that increases the variation in offspring even more than simple reproduction?