empty of future, renew the sign: lucent paradox, ineluctable trace ...

16.12.06

The (Un)Imaginable Future

for SKR


1. Baboon, we have travelled far ...

Look closely at a human embryo within a womb & you will find a cloud of retroviruses swarming the placenta, the remnants of an ancient infection. Without viruses, we might still be laying eggs. For protection, a single layer of an embryo's cells merges into a continuous barrier, a syncytium. Where embryologists spotted spheroid retroviruses budding from cells in a baboon placenta, 30 years ago. A viral gene was making a protein, syncytin, that caused human placental cells to fuse. An artificial molecule, a morpholino, prevented embryos from making the cell fusing proteins. Most inherited viruses are muffled versions of the original infectious forms. The missing viruses vanished when the inherited forms prevented reproduction within the host. HIV may finally be conquered by ancient biological means. It could even lead to a new human species. These few nonprogressors could go on to form the new species. We have the capacity to prevent it being an evolutionary event for the first time.

2. Refugia

Europe is off the hook. The North Atlantic Ocean system ferrying warm water northwards from the tropics is not about to shut down. The warm interglacial period that began when the Ice Age started to wane 17,000 years ago is nearly at an end. Plant & animal species can survive trying times by retreating to safe havens or refugia—places as small as a sheltered valley or a mountain top. Phylogeographers work from both ends—past & present—to determine what species might do in the future. Refugia were the source of colonisation by plants & animals after the Ice Age. The world’s deserts, from Africa & Asia to Australia, have been virtually ignored. In the wet tropics, the climatic & biological requirements of many different species have been determined, & where they held out in the past. The secret is to combine paleo data with genetic information about living species.

3. The Return of the Trees

Forests are increasing across the world after centuries of being destroyed. The increase is most rapid in Spain & the Ukraine, the decrease quickest in Nigeria & the Philippines. The great gains are in China & the United States. Brazil & Indonesia are losing the most. This great reversal could stop the styling of Skinhead Earth & by 2050, expand global forests by 10% or 300 million hectares, the area of India. Where forest coverage is stable. Forests expanded in Europe after the Black Death & diminished again in the Age of Exploration. French forestry records dating back to the Middle Ages show an arboreal renaissance unaffected by population increases. Wealth is an indicator in reversing deforestation. All countries with a GDP per capita higher than Chile’s ($US4600.00) have increased their forest cover since 1990. Replanting in China offsets Brazil’s annual loss of 3.1 million hectares. Indonesia felled a vast area of forest but harvested less timber than the US, which gained growing stock. The main danger to forests is fast-growing, poor populations who burn wood to cook, sell timber for cash & fell trees to plant crops. Harvesting biomass for fuel forestalls the restoration of land to nature.

4. Archaeology of the Brain

Above ground testing of nuclear bombs between 1955 & 1963 led to a big increase of radioactive carbon-14 in the atmosphere around the globe. Levels have since tapered off as the carbon-14 was absorbed by the oceans, plants & animals. A person born in 1963 has twice as much carbon-14 in their system as someone born in 1999. This carbon-14 bomb spike provides a unique opportunity to date human tissue. Carbon-14 levels in the DNA of cells reflect atmospheric levels at the time the cells were born. Levels in the neurons from all areas of the cerebral cortex are as high as the atmospheric levels at the time of each individual’s birth. Neurons of the cerebral cortex are thus the ones you were born with. We don’t make new neurons in this decision making region of the brain. Having a permanent population of cells that store information about language, maths & logic over a lifetime may be better than growing new na├»ve cells that have not been exposed to years of experience, as is the case with fish & frogs. Human muscle cells are fifteen years old, bone, ten years, liver, two, red blood cells, 120 days, outer skin layer, two weeks, gut lining cells, five days; unlike your hippocampus, which regenerates, your front brain is the same age as you are.


Baboon ... adapted from: The Australian, 1.11.06;

Refugia adapted from: The Australian, 8.11.06;

The Return of the Trees adapted from: The Australian, 22.11.06;

Archaeology of the Brain adapted from: The Sydney Morning Herald, 14.12.06.

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