Adventures in Science

Polished sphere of amber with a beetle inclusion. (source)

Amber is fossilized tree resin from prehistoric conifer trees. The slow and sticky resin oozed out of a tree when it suffered damage and protected it like a gooey bandage. Eventually this resin would harden and shed off the tree where it would collect as part of the debris and sediment of the ancient forest floor. Over eons of time the resin matured chemically and fossilized into the hard plastic-like material that we know today as amber.

Fossilized tree resin from hundreds of millions of years ago is exciting, yes, but it’s what has been found in amber that is so much more riveting. Trapped within these organic stones you can often glimpse perfectly preserved organisms from the prehistoric past. Some of these unlucky deep time travelers include insects, spiders and their webs, seeds, pine needles, flowers, frogs, and even a lizard. These ensnared creatures and plant matter–known as inclusions–have been dated up to about 150 million years ago. Most of these organisms are now extinct but can be studied and classified by comparing them with current known species or known fossils.

Rock fossil of a feathered dinosaur (source)

Many of the most intriguing amber fossils are found in Canada and include a few types of feathers and protofeathers. Scientists collected and studied 11 samples of amber containing feathers and found that they were seeing a range of plumage that showed a development from primitive protofeathers to more complex feathers like those found on modern birds. They found that  some of these feathers are similar to the ones seen in rock fossil impressions of feathered dinosaurs. The more advanced feathers may have come from early birds. If you like reading about dinosaurs, amber, or prehistoric life, you will enjoy reading the original scientific paper by the scientists who are studying these fossil feathers in amber.

Possible dinosaur protofeathers.  (source)

Above are just two stages of the known stages of feather evolution. On the left are protofeathers which are very primitive and look like very fine hairs or filaments. Researchers have nicknamed these simple protofeathers “dinofuzz”. They are even studying the pigments–color-producing particles–on these feathers. Those pigments from feathers have been found in rock fossils as well, as seen in this video from researchers at Yale University.

If you have ever seen or heard about the movie or book “Jurassic Park” you may have heard that it might be possible to take DNA from an organism that has been preserved in amber. Unfortunately, at this time, that seems unlikely. DNA breaks apart quickly once an organism dies. However, amber is a fantastic preservative and if we are going to find ancient DNA somewhere it is most likely to come from just such an ideal source. Some scientists have had promising results in extracting bits of DNA from amber; however, it is a difficult and tricky process and other scientists have had trouble getting the same results. It could be possible to get a snippet or two of DNA but the DNA of a whole organism from many millions of years ago might be impossible at least for the foreseeable future.

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