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SPEC'S QUATERNARY PERIOD (c.1,700,000 - 0 b.p)
A little less than 2 million years ago, the Earth entered what can only be described as a climatic
rollercoaster, a time which marked the end of the Neogene Period and the start of the Quaternary
Period. Thus began a series of drastic cooling phases for the planet, the famous Ice Ages.
In RL, the Quaternary is divided into two epochs - the Pleistocene and the Holocene (the time
from the last glaciation up until the present day). Although these units are sometimes
used on Spec for purposes of convenience, it should be noted that:
a) the biotic changes that have characterised the Holocene on RL are far less profound on Spec (see below)
b) evidence collected on both worlds suggests that this current phase of mild climate is little more than a short interglacial period and that the Specworld is heading towards yet another round of glaciation. On RL the activities of industrialised humanity appears to be reversing this situation.
From about 1.7 million to 11,000 years ago, the world experienced at least four major glacial episodes. Great sheets
of ice spread out from the Arctic, covering much of North America and Europe. Increased glaciation also occured in the southern hemisphere although to a much lesser extent. At its peak, about 44 million sq km of the planet's surface was ice-bound. With so much water locked away, sea-levels fell by over 100 metres, resulting in the devastation of local marine faunas
and the creation of several land-bridges, including those across the Bering Strait, the English Channel, the Torres Strait, and the Sea of Japan. After a time, the ice would retreat and the world would be given the brief respite of an interglacial that saw the return of milder conditions.
The effect of the Ice Ages, both on the landscape and the creatures that inhabited it, was profound.
The flow of the glaciers carved great valleys in the Earth, while accumulating boulder clays and
moraines. Strongs winds near the ice sheets carried fine-grained dust to distant lands, resulting
in thick loess deposits in Africa, central Asia, and midwestern North America.
With regards to the vegetation, the coming of the Ice Age heralded the arrival of vast areas
tundra in the north, providing a rich feeding ground for cold-adapted grazers, such as polar
therizinosaurs and large paraselenodont mammals. In the lower latitudes, some areas acquired
lush woodlands while others faced increasing aridity. When the ice retreated, temperate forests
returned to the high-latitudes, accompanied by herds of hadrosaurs. Each phase of glaciation
and interglacial proved to be of benefit to some organsisms at the expense of others. The
ranges of some animals expanded while other were reduced to scattered populations only
to have the situation reversed when the extent of the ice shifted.
Macropokemus robustus
In all physical aspects, the progression of the Ice Ages of Spec appears to have been identical to that
of RL. However, with regards to life on the planet, there is one startling contrast. The conclusion of
the last Ice Age on RL broadly coincided with the extinction of many large terrestrial animals -
mammoths, giant deer, ground sloths, sabre-tooth cats, etc. As far as can be determined, such
a phenomenon did not occur on Spec. 11,000 years ago, the ranges of many tundra-dwelling
dinosaurs, such as the arctotitan, were certainly greatly reduced, often accompanied by a
reduction in body-size. Some areas also experienced localised extinctions, particularly
North America, which lost its ceratopsians as great areas of woodland were converted to open
praries. But on the whole, probably over 90% of all of Specworld's Ice Age megafaunal
genera are still alive and well.
This evidence points the finger of blame firmly at humanity for the extinction of the great beasts
of our own home time-line. Spec, never subjected to the curse of the killer ape, remains the abode of giants.
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