GOOD MOTHER DINOSAUR

The image below is a photo of the exhibit panel. Following it is a transcript of the panel.

Photo of the panel from the exhibit.

Fossils show that some extinct dinosaurs took care of their young, just as their living relatives do.

Since parenting behavior occurs in living dinosaurs (birds) and in their close relatives (crocodiles), scientists theorized that extinct dinosaurs cared for their eggs and offspring. The recent discovery of a Maiosaura nesting colony, with eggs and young still in the nests, confirmed that theory.

Maiosaura (my-ah- SOR -ah): a 30-foot-long plant-eating dinosaur from North America

"good mother dinosaurs" built nests that were:

  • excavated into mounds of mud
  • six feet in diameter
  • spaced 30 feet apart (length of an adult)
  • heated by decaying plants
  • filled with 20 to 25 eggs, laid in a circular pattern

When? 75 million years ago

Parenting in Ancient Dinosaurs
A colony of eight dinosaur nests, built by the duckbill Maiasaura , was found in Montana in 1978. From this discovery, we learned that Maiasaura babies (18 inches long when first hatched) remained in the nest until they grew to about four feet long.

PICTURE CAPTIONS:

  • These baby dinosaurs may have been able to stand in the nest, but they couldn't go far! Incomplete ends of bones in the knees, ankles, and elbows of three-foot-long Maiasaura juveniles are like those of modern chicks that remain in the nest, cared for by adult birds. One or both Maiasaura parents may have fed the young ones in the nest (most likely with previously chewed plants, seeds, and berries).
  • Diagram showing common ancestry and evolution of crocodiles, dinosaurs, and birds from organisms with vocalization, breathing while running, and parental care. Evolution of dinosaurs and birds is where upright posture and s-shaped neck branch off.