By Stephan Kamrad
Roughly 5,000 years ago, copper-made tools replaced ones made from polished stones, marking the transition from Neolithic to Bronze Age. 250 human generations were born and have died since then but this is also the sprouting day of the oldest tree still alive today: A great basin bristlecone pine (Pinus longaeva) growing in the White Mountains in California celebrated its 5063rd birthday this year! The species grows in the subalpine regions of California, Nevada and Utah and is famous for its longevity. Many old bristlecone pines grow in the White Mountains but the location of the most ancient ones is kept secret for their protection. One particular tree, Methuselah, was long thought to be the oldest tree, but it turns out it is only 4846 years old. A whole 217 years younger than the forest’s nameless elder, but still a lot older than its eponym: Methuselah, grandfather of Moses, who allegedly lived for 969 years.
The bristlecone pine’s secret is its resinous wood that is degraded only very slowly in the cold climate. Damaged, old parts of the bark and wood protect the still functioning parts and get worn away slowly by ice and wind. This makes age determination less than trivial because traditional ring-counting underestimates the age of the tree. Instead it involves a combination of methods such as cross dating, historic records and radiocarbon dating.
However impressive this record as oldest individual tree may be, it is almost cute when compared to another plant living in the Fishlake National Forest in Utah. Pando (Latin for I spread) is a male quaking aspen (Populus tremuloides). The organism is 80,000 years old and weighs almost 6 million kilos. It is a single plant with an underground root system spanning over 46 hectare (about half a square kilometres). From this root system a large number (over 40,000) trunks originate, but usually die after a few hundred years, being replaced by new trunks.
No animal comes even close to these ages. The oldest mammal is the bowhead whale. Tips of ancient harpoon weapons, now long out of use, found in whales and biochemical analysis determined that the whale was over 200 years old when captured. On a funny note, the method for determining the age of blue and fin whales involves counting the layers of wax in the whale’s inner ear; just like counting rings in a tree!
The oldest terrestrial vertebrate known to us was Adwaita, an Aldabra tortoise who grew an estimated 255 years old. During the colonialisation of India, she belonged to the British general Robert Clive of the East India Company who kept her as a pet on his estate. Adwaita died in the zoo of Calcutta in 2006.
In the end, as it is so often in biology, the record is held by unicellular organisms. Recently, researcher found bacteria living in the sediment of the ocean that are millions of years old. Substrate is extremely scarce, putting them in a zombie-like state of barely detectable metabolic activity and cell division about once every 10,000 years (E. coli: 20 minutes).
For hunting records in biology, the same applies as for hunting records in sports: They are meant to be broken! Despite what the overwhelming amount of information on the internet may suggest, there are still many blanks on the map. Large areas of rainforest and desert were never set foot and are only known to us as satellite images and the deep sea is said to be less known than the surface of the moon. Who knows what we may find there.