Explore Milwaukee County (Click on picture) Milwaukee County, created in 1834 as a territorial county, is derived from a Native American word Mahnawaukee-Seepe meaning gathering place by the river.. Located in southeast Wisconsin, the county seat is Milwaukee.
The Cretaceous-Tertiary extinction event, or the K-T event, is the name given to the die-off of the dinosaurs and other species that took place some 65.5 million years ago. For many years, paleontologists believed this event was caused by climate and geological changes that interrupted the dinosaursâ food supply.
In the oceans, the KâPg extinction killed off plesiosaurs and the giant marine lizards (Mosasauridae) and devastated fish, sharks, mollusks (especially ammonites, which went extinct) and many species of plankton. It is estimated that 75% or more of all species on Earth vanished.ost paleontologists now agree that an asteroid did hit the Earth at approximately the end of the Cretaceous, but there is an ongoing dispute whether the impact was the sole cause of the extinctions. There is evidence that there was an interval of about 7012946728000000000â 300 ka from the impact to the mass extinction.