lower1. 1  to cause to descend; let or put down: to lower a flag. 2  to make lower in height or level: to lower the water in a canal. 3  to reduce in amount, price, degree, force, etc. 4  to make less loud: Please lower your voice.
Biggest Whale-Basilosaurus (60 Tons). Basilosaurus (Nobu Tamura). Unlike the other mammals on this list, Basilosaurus can't lay claim to being the largest-ever of its breed--that honor belongs to the still-extant Blue Whale, which can grow to as much as 200 tons.
Both were among the largest predatory mammals of all time. The largest member of the extinct Notoungulata, and the superorder Meridiungulata, was Toxodon. It was about 2.7 m (8 ft 10 in) in body length, with an estimated weight up to 1,415 kg (3,120 lb). Taeniolabis taoensis is the largest non-therian mammal known, at a weight possibly exceeding 100 kg. Notes