The three different ways mammals give birth - Kate Slabosky

View full lesson: http://ed.ted.com/lessons/the-three-different-ways-mammals-give-birth-kate-slabosky All mammals share certain characteristics, like warm blood and backbones. But despite...

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What do these animals have in common?More than you might think.Along with over 5,000 other species, they're mammals,or members of class mammalia.All mammals are vertebrates, meaning they have backbones.But mammals are distinguished from other vertebratesby a number of shared features.That includes warm blood,body hair or fur,the ability to breathe using lungs,and nourishing their young with milk.But despite these similarities,these creatures also have many biological differences,and one of the most remarkable is how they give birth.Let's start with the most familiar, placental mammals.This group includes humans,cats,dogs,giraffes,and even the blue whale, the biggest animal on Earth.Its placenta, a solid disk of blood-rich tissue,attaches to the wall of t...