Amber Finds Reveal...
Amber is bringing back a treasure-trove of riches for biologists, whether they call themselves paleoecologists (students of ancient ecology), systematists (students of taxonomy), or hyper-jargonifiers. That's because amber research has opened new windows on the past. Let's peek through.
- Entomology (bugs to you and me)
- Insects trapped in amber show what they used to look like and where particular species used to live. A species of termite found in Dominican amber, for example, only exists now in Australia. Thus amber can help uncover animal migration patterns, and reveal information about climate, sea level, environmental conditions, and the presence or absence of other animals and of plants.
- Genetic information
- DNA -- the chemical which carries the genetic code -- can be recovered from many biological samples, and even from ancient amber. By looking at specific parts of the code, scientists can compare the "spelling" of the code to that of existing organisms (small changes occur through the years in many well-known genes). Then, by using estimates of the rate of change per year, they can calculate whether two samples are from the same species, from closely related species, etc.
These techniques of "molecular genetics" can also be used to identify species and restructure the tree of life. In other words, they can demonstrate how organisms are related, based not on their appearance or structure, but on how their DNA has changed over the years.
- Whole organisms
- (The Jurassic Park scenario, again). Boring. Nobody's seriously talking about resuscitating dinosaurs -- or even moths. But some whole organisms have been recovered from amber. Jump ahead to read all about it!
In the midst of the gathering excitement about amber, scientists would like to answer questions like these:
- Does amber accumulate gradually or suddenly?
- David Grimaldi, of the American Museum of Natural History, thinks the deposits in the Dominican Republic resulted from disturbances. Say a tropical storm broke tree branches, allowing large amounts of resin to exude. Some of this resin, the amber we find today, would be the stuff that was covered by sediment.
What kind of stuff does not get trapped in amber?
- This would tell us what kind of a partial picture we are getting of the ancient world?
- Are there other, unrecognized preservatives out there in nature?
- And how do amber discoveries mesh with the information from other known natural preservatives?
- How real are the results?
- Is some systematic error being made that throws off all the DNA results? As we'll see shortly, microbiologists must make sure they're not just propagating modern bacteria when they extract "ancient bacteria" from amber.
You can bring ancient critters to life?