I just got back from the National Science Teachers Association meeting in Denver and besides for (and including) the sunny, 70° weather, it was a great experience. It was fun and kind of exciting to go to workshops and see what people were doing in science education. It was very entertaining to go through the exhibit hall and see what science manufacturers are making to sell to educators. (You gotta see the foot-long alligator that grows to 7-feet-long overnight when you add a gallon of water.) I noticed that the science teachers where all signing up for these raffles that many of the manufacturers were offering, so I did too. Hey, you never know. Later I got an email that I had won a video ipod. You have to love that. Even though it was from a company that promotes educational awareness of how good fertilizer is for the world… Hmmm…
My lecture went pretty well too. About 50 educators came and they seemed to respond well to what I had to say about developing nature trails for their schools and several stayed afterward to discuss it. It gave me some ideas about how to expand on the Making Tracks Challenge among other things. Now I have to figure out how to get schools to actually make a commitment to work on their nature trails. I have incentives. I have information. I just need to get them on board. Any ideas?
The big science revelation of the trip came at a most unexpected moment. I went to a talk by the The Children’s Book Council and how they judge books to be recommended for the Outstanding Science Trade Books for Students K-12. They had rejected a book because it had listed only 5 Kingdoms of life. They said the reason was that it was now accepted in the scientific community that there were only three kingdoms.
Woah! I sat up in my chair – 3 Kingdoms?! Since when? The speaker showed me an explanation by the Children’s Book Council that said that indeed there are now 3 Kingdoms. That’s crazy, I thought, you can’t lump animals, plants, mushrooms, bacteria and algae into 3 Kingdoms. Had I been asleep through some new major taxonomic revolution? I had to go home and research this.
It turns out that I haven’t been asleep, but clearly some changes have been creeping up in taxonomy in the last five years. This is what I have discovered.
A new Phylogenetic Classification System, called the Woesian three domains is being accepted in classification circles. It does indeed lump animals, plants, mushrooms, bacteria and algae into one group, but not as one Kingdom as the Children’s Book Council speaker mistakenly suggested. They are grouped together as all Eukaryotes, which they are. They are divided from the Prokaryotes, which make up the two other “domains” or “Super-kingdoms.” There is a huge difference here and I will explain how.
Eukaryotes have their genetic material (DNA) confined in a distinct nucleus surrounded by a nuclear membrane inside all our cells. Each organelle, in fact, is a distinct membrane bound unit, carrying out its function in our cells, whether it is respiration or amino acid production.
The more “primitive” organisms, like bacteria, (previously the Kingdom Monera), are the prokaryotes. Prokaryotes do not have a membrane-bound nucleus but carry all their DNA in an area referred to as the nucleoid. Prokaryotes also do not have distinct organelles. Metabolic functions are free floating or bound to the outer wall within the cell. Prokaryotes may be primitive but they can survive in some very hostile environments that existed on early Earth. This makes them amazing survivors.
The change happened when, a few ago, a prokaryotic organism that lived in the extreme temperatures of hot springs and volcanoes (and was formerly thought to be a Monera bacteria) was discovered through genome evaluation to be something quite unique. These were called “Archaea” named for their archaic origins as evolved from the oldest organisms to have lived on earth. At first Archaea was considered a 6th Kingdom, but now a new classification grouping has been adopted as proposed by microbiologist Carl Woese of the University of Illinois.
The new system consists of three “domains” or “Super-Kingdoms” as mentioned above.” The three domains are Eukarya, Eubacteria (true bacteria), and Archaea.
Eukarya Domain (or Super-Kingdom) includes the 4 Kingdoms of eukaryotes – animals, plants, mushrooms, and algae.
Eubacteria Domain or True Bacteria Domain (or Super-Kingdom) includes – bacteria.
Archaea Domain (or Super-Kingdom) includes – archaea.
So there it is, in all its amazing and blinding glory. Well… I thought it was pretty exciting anyway. But remember, I study what’s under rocks for fun…