Whatever lives in the sea nowadays can’t be compared with the huge monsters that dominated the depths millions of years ago. And by “monsters” we mean long-extinct marine reptiles and dinosaurs. Since many people are better acquainted with the land-roaming giants of the past, this video will open your eyes to those that ruled the waters! Did you know, for example, that pliosauruses were real giants, with the largest species weighing more than 30 tons and growing up to 40 feet long? Also, this animal had an incredibly strong bite. In fact, it was four times more powerful than that of the mighty T-rex!