Tuesday, January 6, 2009

Becoming a Fossil

Many in the mainstream scientific community have pointed to the fact that there is no evidence of a North American great ape in the fossil record as proof that the sasquatch could not be a real animal. Below is a snippet from an article written by Olivia Judson of "The New York Times" regarding how difficult it is to "become a fossil".

It's hard to become a fossil, to leave a tangible record of your presence on
the Earth millions of years after you died. Most of us swiftly get recycled
into other beings. After all, the competition for corpses is fierce. Species
of bacteria
, worms, ants, flies, beetles and even some butterflies have a
taste for rotting flesh. And that's without mentioning larger scavengers,
like vultures, hyenas and mongooses.

The disappearance of a body can be rapid. To give one of my favorite
examples, in the tropical forests of the Congo, an adult male gorilla - all
150 kg (330 lbs.) of him - will be reduced to a pile of bones and hair
within 10 days of his death. Within three weeks, there will be nothing left
but a few small bones. And this is without the help of creatures like
hyenas, which pulverize and eat the bones of all but the largest animals.
(That's why hyena scat is white: it's the remains of powdered bone.)

But evading Nature's undertakers is only the first step in becoming a
fossil. If you want to be preserved for millions of years, you also have to
choose the right place to die. If you're lucky, you'll have a quick burial
in, say, the silts and sediments of a river bed, or under volcanic ash.

For many environments can never yield fossils. Die on top of a mountain, for
example, and your fossil hopes are slim. The reason is that mountains don't
bury, they erode. (You might get frozen in ice, in which case you may last
as long as the ice does, which may be several thousand years; but it won't
be several million. Ice is for those with modest ambitions for immortality. )
Likewise, if soil is too acidic, bones dissolve. That's why forest animals
leave few fossils: forest soil tends to be acidic.

Even if you manage to die in the right place, you'll have a better chance of
surviving in death if you have the sort of body that can leave hard remains.
In the fossilization stakes, animals with shells - like oysters - have an
advantage over those without (jellyfish, say).

All this means that the fossil record of the Earth is inherently skewed. For
instance, river deltas are great places to get buried and preserved. So
animals that lived in or near them are much more likely to make it into the
fossil record than most other creatures; as a result, we have river-delta
fossils in much greater numbers than most other types. But during life,
those animals were by no means the most numerous. As one friend put it, it's
like making an inventory of current North American wildlife based on what
you find at the mouth of the Mississippi.

In light of this, the fossil record we do have becomes the more amazing.
Yes, it has limitations. Yes, there are many organisms that we can never
know about, for we will never know they existed. They breathed, and changed
the atmosphere; they preyed on other beings; their carcasses became food,
and altered the composition of the soil; but they left no physical trace, no
clues to what they looked like, to the lives they led, the mates they
seduced, the songs they sang.

Yet it is not surprising that the fossil record is incomplete - how could it
be otherwise?

You can access the article in its entirety here. Please note a free registration is required in order to view the article.

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