A computer generated depiction of Juramaia sinensis shows how the creature may have moved CHAPTER ONE Jurassic Mother from China One hundred and sixty million years ago MYA a tiny animal moved through the treetops Its front paws grasped the branches as it searched for food Worms became quick snacks With its sharp teeth the small furry animal now called Juramaia sinensis cracked the exoskeletons of insects and ate them This was the late part of the Jurassic period 201.3-145 MYA In some regions large plant eating dinosaurs like brachiosaurs and
A kangaroo joey continues to use its mother's pouch to feed after it is able to walk
meat eating dinosaurs such as allosaurs dominated the landscape Archaeopteryx a bird that had teeth and a long tail flew through the air At night in the cover of the trees the tiny J. sinensis could hide from predators and seek its own prey Juramaia sinensis which means Jurassic mother from China is the name scientists gave this animal It weighed less than 0.5 ounces 15 g Its skull was 0.87 inches 22 mm long It looked like a shrew and could climb into the trees Juramaia sinensis was also a placental mammal Scientists know that placental mammals often called eutherian mammals and today's marsupials evolved from a common ancestor Marsupials are mammals that give birth to immature young that often shelter and feed in the mother's pouch Kangaroos and opossums are marsupials Placental mammals have a longer period of growth in the womb so they give birth to more mature young These young receive nutrients in the womb through a complex organ called the placenta Dogs horses and human beings are placental mammals The J. sinensis specimen is the oldest known fossil of a placental mammal It was discovered in China's Liaoning province in 2011. The fossil consists of only a partial skull and skeleton in addition to impressions of soft tissue including hair in the surrounding rock This fossil
