More than 100 years after joining the Museum’s archaeological collection, a remarkable set of 11th-century pottery excavated in New Mexico’s Chaco Canyon is at the center of a delicious discovery.

Found at Pueblo Bonito, one of the great ceremonial complexes of the Ancestral Pueblo peoples, the rare ceramics were collected for the Museum by George Pepper at the turn of last century. Only recently, however, have researchers looked to the set to search for chemical traces of the vessels’ long-lost contents. The results were electrifying: tests revealed the presence of theobromine, the biomarker for cacao, confirming the earliest known use of chocolate north of the Mexican border.

In the last few weeks, 13-year-old Aidan — a 2011 Young Naturalist Award winner whose scientific project, described in his essay The Secret of the Fibonacci Sequence in Trees, garnered much attention for examining whether patterns of tree leaf distribution were linked to more efficient sunlight collection—received another important lesson in his young scientific career.

Thylacinus cynocephalus goes by many common names: Tasmanian wolf, Tasmanian tiger, zebra dog, pouched wolf, and marsupial dog, among others. A quick look at the animal explains the confusion. Shaped like a dog, striped like a tiger or zebra, pouched like an opossum, and reputed to behave like a wolf, it became many different creatures in the popular imagination.

But the thylacine is, or was, a unique species. Now considered extinct, the thylacine was a carnivorous marsupial that lived in Tasmania and fed primarily on kangaroos, wallabies, small mammals, and birds. Nocturnal and shy, it was seldom seen by humans. Nonetheless, beginning in the 19^th century, settlers believed the animals threatened their livestock and, spurred on by a bounty offered by the government, hunted them relentlessly. Despite numerous unconfirmed reports of sightings in recent decades, no definitive sightings have occurred since the 1930s.

They are some of the rarest of rare artifacts: fossil dinosaur eggs with the embryo still inside. And they are prized for what they can tell paleontologists about the adults that laid them.

The exhibition The World’s Largest Dinosaurs features a scale model of a nest found at Auca Mahuevo, Argentina, one of the largest known dinosaur nesting sites in the world. While it isn’t always possible to figure out which dinosaur laid a particular egg, in this case, an embryo within an egg found at Auca Mahuevo site allowed scientists to identify these eggs as those of titanosaurs, a group of sauropods that included such species as Ampelosaurus and Saltasaurus. Herds of female titanosaurs are thought to have laid the thousands of eggs — 15 to 40 at a time — in shallow nests dug out with their huge feet in dry mud and sand over miles of ground at Auca Mahuevo.

Almost every star is now thought to form with a planetary system around it. But just how rare a phenomenon are habitable planets? In this podcast, Massachusetts Institute of Technology professor Linda Elkins-Tanton discusses what is currently known about planetary formation—and what is needed to encourage the development of life.

Dr. Elkins-Tanton’s talk, “A Hitchhiker’s Guide to Habitable Planets in Our Galaxy,” was recorded at the Museum on April 11, 2011.