| By Maryann Whitman
Welcome to the Anthropocene
The classic presentation of the biomes
of the Earth, as seen in all our current
ecology texts, has been based on abiotic
environmental conditions, like climate,
and the productivity of the dominant
vegetation. The eight major biomes have
been: Tropical Rainforest, Tropical Savanna,
Desert, Chaparral, Grassland, Temperate
Deciduous Forest, Temperate Boreal Forest,
and Arctic and Alpine Tundra.
In the December
13, 2007, issue of Frontiers
in Ecology and the Environment, the peer-reviewed
publication of the Ecological Society of
America, a new way of looking at our
planet was presented. Global data from
satellites and land management statistics
were used to map a new system of “anthropogenic
biomes,” “anthromes,” or “human
biomes” that describe the biosphere
as it exists today, the result of human
reshaping of ecosystems.
Anthropogenic biomes
are not simple vegetation or climatic categories,
and are best characterized as heterogeneous
landscape mosaics combining a variety of
different land uses and land covers. The
major anthropogenic biomes suggested are:
Dense Settlements, built environments, very high
populations; Villages, agricultural settlements
(>100 persons
km2); Croplands, Crops Mixed With Other
Uses, Rangelands, grazing, minimal crops & forests;
Forested, forests with humans & agriculture;
Wildlands, without humans or agriculture.
This
publication may well spur a paradigm shift
in approaches to conservation, restoration
of “natural areas” and concerns
for biodiversity. The Wild Ones’ approach
to natural landscaping will surely find
a comfortable niche. (See the article in Frontiers
in Ecology and the Environment, available at www.ecotope.org/people/ellis/papers/ellis_2008.pdf.)
Population
Consider this: Last year a human-like fossil
was found in the mountains of northern
Spain that is thought to represent the
last common ancestor of Neanderthals and
modern man. The new fossil, tentatively
classified as Homo
antecessor (Pioneer Man), was determined
to be 1.3 million years old. By the year
500 BCE, the population of genus Homo was estimated to be 100 million. Around
1835 there were 1 billion of us. In 1960
there were 3 billion. And in January, 2008,
the population of the planet was estimated
at 6.778 billion.
Bugging bees
Scientists at Queen Mary, University of
London, are bugging bees – with minuscule
tracking gear to better understand these
brainy bugs.
Biologist Nigel Raine said, “Bumblebees
have a relatively small brain – they
have about 950,000 brain cells, humans
have 100 billion – but they can achieve
rather impressive feats of learning and
memory given what they have got.”
Recent
research has revealed that bees are able
to recognize individual human faces, which, according
to Dr. Raine, is not that surprising given
the daily challenges they face while foraging.
He explained, “When you think about
your average park or meadow, there might
be dozens of species of flowers which are
all different in terms of color and shape
and scent, and they are all differing in
the rewards they are providing.
“Ultimately,
the bees’ job is
to go and find the best rewards from these
flowers, and they have to be flexible and
learn and remember information, all the
while making and breaking associations. This is
all really quite complicated.”
Their
navigational skills are impressive, too. “These
tiny animals leave their nests, fly back
and forth between flowers, then they are somehow
able to add all of these vectors together
and fly back to their nest in a straight
line,” said
Dr. Raine.
In the wild, bees will often
visit flowers in a sequence that they repeat
time and time again.
This makes sense biologically,” explained
Dr. Raine. “If you take the nectar out
of the flowers, they will begin to refill,
so you do not want to visit that flower again
until it is as full up as possible.”
But what is really clever, he adds, is
that the bees will work out shortcuts so
that they can create the shortest, most
efficient journey possible.
“We are really
interested to see how they form these routes – we
call them “traplines” – and
we are using technology to help us to understand
how the bees are performing these feats
of spatial learning.”
Bees around Europe
have suffered a huge drop in numbers in
recent years: three species in the UK have
recently become extinct; another eight
are in serious decline.
Scientists believe that
habitat degradation around their nesting
and foraging sites could be to blame.
Dr.
Raine said, “In terms of biodiversity,
bumblebees are hugely important pollinators,
yet most species are becoming increasingly
rare.
"Understanding the differences in how
they actually forage is very important
for aiding conservation.”
It’s a weird and
wonderful world
Scientists at Georgetown University have
demonstrated that learning and memory in
butterfly caterpillars is not only possible,
but that these memories are retained by
the butterfly after metamorphosis. Metamorphosis
is that poorly understood period of life
when a caterpillar enters into a pupa or
chrysalis phase and emerges a winged butterfly.
What happens in the chrysalis is even more
mysterious than what happens to Superman
in the phone booth. That memories survive
this “molecular
soup” stage is just as stunning.
Conservation
applications of this discovery easily progress
into the arena of science fiction. Maryann
is Editor of the Wild Ones Journal, and
comes to the position with an extensive background
in environmental matters of all kinds.
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