This article is the third in a series in which I am presenting research on some of the more obscure members of our global ecosystem. I believe that by understanding the complexities of our global flora and fauna, we are in a better position to promote respect and conservancy for our natural resources.

     It is clear that our ecosystems are incredibly complex and interwoven. For every small disruption that we make to the health of the planet, there are repercussions to the rest of the ecosystem. And with major disruptions such as climate change, the effects on our ecosystems is unparalleled and potentially catastrophic.

     Hence, in this series, I am asking the question, who is this obscure representative of plant or animal life, and how does he fit into the larger ecosystem that we need to protect? So I turn to the rare and mysterious Pyrolobus Fumarii. Pyrolobus fumarii is famous for being the living organism that can survive at the most extreme heat on the planet, 113 degrees Celsius. It is known as an "extremophile" because it can survive at extreme temperatures that would kill most other life forms. It is in the Domain of the Archaea and it lives deep in the ocean, in black smoker vents of the Earth's crust.

The relevant taxonomy for the Pyrolobus is:

Domain: Archaea

Phylum: Crenarchaeota

Class:  Thermoprotei

Order: Desulfurococcales

Family: Pyrodictiaceae

Genus: Pyrolobus

     By way of background, the Earth was formed around 4.5 billion years ago, during Hadean time (4.6 to 4 billion years ago). The Archean Eon was from 4 billion to 2.5 billion years ago. During this time period, life first appeared on earth 3.5 billion years ago, and Prokaryotic cell fossils date to this time, but whether they are archaea or bacteria cannot be determine from the fossil shapes. Carl Woese wrote to Francis Crick in 1969 that he wanted to use the cell's internal fossil record (its RNA) to extend our knowledge of evolution backward in time by a billion years or so.

     Until the 1970s, all life was classified as either in the Eukaryote Domain (having cell nucleus) or the Prokaryote Domain (not having cell nucleus).  However, the work of scientists Carl Woese and George Fox in 1977 showed that not all prokaryotes belonged in the same domain: which led to our now having three domains: the Eukarya, the Bacteria and the Archaea. It was a cousin of Pyrolobus that was the first Archaea to be genetically studied by Carl Woese. That Archaea was Methanocaldococcus jannaschii.

     The Archaea are prokaryotes but their RNA shows that they are different from Bacteria. The classification of archaea as a new field is based mostly on the study of RNA sequencing. There are two main phyla of Archaea, the Euryarchaeota and Crenarchaeota. Archaea are different from Bacteria because they branched off from each other around 3.5 billion years ago. In fact, the name "Archaea" comes from the Greek word for "ancient things". Prokaryotic cells date to around 3.5 billion years ago. Actually, it is said that the Archaea are more closely related to humans than to Bacteria at this point.

     Pyrolobus fumarii is one of the most interesting forms of Archaea. It is known as an "extremophile" because it can survive at extreme temperatures that would kill most other life forms. Pyrolobus can survive at 113 degrees Celsius, which is the highest known temperature for life to survive on Earth. It was discovered in a "black smoker" near the bottom of the Atlantic Ocean. A black smoker is a type of vent at the bottom of the sea that is a crack in the planet's surface. Out of the crack comes very hot water heated below the crust of the earth. Black smokers give off a cloud of hot black materials along with the superheated water.

     Pyrolobus fumarii was first discovered in 1997. It is possible that the last common ancestor or the Archaea and the Bacteria was a "thermophile" that lived in extreme temperatures. Pyrolobus is an unusual group of Archaea, extending the upper temperature limit for life to 113 degrees Celsius. It grows between 90-113 degrees, with an optimum temperature at 106 degrees Celsius. Because these "extremophiles" survive at previously unheard of temperatures, science is looking at new technologies, such as heat-resistant materials and other uses.