Do you
know the total stock of species on planet Earth? I don’t know. I doubt if
anybody knows. It is a matter of estimate. Though no one knows for sure the
total stock of the earth’s species, species are discovered annually. Species
are of critical importance in the cycles of major elements. The highlight of
this post is the 2014 top ten new species which I hope will be of interest to
you as a lover of nature.
The word
"biodiversity" is a contracted version of "biological diversity".
The Convention on Biological Diversity defines biodiversity
as:"the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and
the ecological complexes of which they are a part; this includes diversity
within species, between species, and of ecosystems."
Thus,
biodiversity includes genetic variation within species, the variety of
species in an area, and the variety of habitat types
within a landscape. Perhaps inevitably, such an all-encompassing definition,
together with the strong emotive power of the concept, has led to somewhat
cavalier use of the term biodiversity, in extreme cases to refer to life or
biology itself. But biodiversity properly refers to the variety of living
organisms.
Biological
diversity is of fundamental importance to the functioning of all natural and
human-engineered ecosystems, and by extension to the ecosystem services that
nature provides free of charge to human society. Living organisms play central
roles in the cycles of major elements (carbon, nitrogen, and so on) and water in the
environment, and diversity specifically is important in that these cycles
require numerous interacting species.
General
interest in biodiversity has grown rapidly in recent decades, in parallel with
the growing concern about nature conservation generally, largely as a
consequence of accelerating rates of natural habitat loss, habitat
fragmentation and
degradation, and resulting extinctions of species. The IUCN Red List estimates
that 12-52% of species within well-studied higher taxa such as vertebrates and
vascular plants are threatened with extinction. Based on data on recorded
extinctions of known species over the past century, scientists estimate that
current rates of species extinction are about 100 times higher than long-term
average rates based on fossil data. Other plausuble estimates suggest that
present extinction rates now may have reached 1000 to 10,000 times the average
over past geologic time. These estimates are the basis of the consensus that
the Earth is in the midst of the sixth mass extinction event in its history;
the present extinction event is termed the Holocene Mass
Extinction.
Biodiversity
is most frequently quantified as the number of species; estimates of the number
of species currently living on Earth range widely.
The
following is a report on the 2014 top ten new species by Jennifer Frazer, for
National Geographic:
(A raccoon relative, an ice-loving
anemone, and a tough but tender shrimp head up this year's list.)
The olinguito is
the first carnivore species to be discovered in the Western Hemisphere in 35
years.
Forty years ago,
Ringerl the olinguito had a problem: Her human matchmakers kept setting her up on bad
dates. How bad? They weren't even males of her own species.
That indignity
was belatedly righted last year when her species—a raccoon relative unique to
the cloud forests of Colombia and Ecuador—was properly identified at last as
Bassaricyon neblina: the first new carnivorous mammal species described in
the Western Hemisphere in 35 years
The realization
also earned olinguitos a spot on the 2014 Top 10 New Species list, published today by
the State University of New York's College of
Environmental Science and Forestry's International
Institute for Species Exploration.
UNUSUAL SUSPECTS
This year's list
includes a lineup of startling creatures notable for their scrappiness,
weirdness, thrift, and sloth. For instance:
A new sea
anemone—Edwardsiella andrillae, discovered accidentally by a geology
team testing an undersea robot—grows upside down from burrows in the Antarctic
Ross Ice Shelf, two dozen tentacles dangling into the water below. It's the
first species of anemone known to grow in ice.
There's also a
new species of ghostly, raptorial skeleton shrimp, an eighth- to a
tenth-of-an-inch long (two to three millimeters), collected from a cave on
Santa Catalina Island off California. Called Liropus minusculus, they
seem to live to pick fights with each other, yet are also caring mothers.
And then there's
a fierce-looking, well-camouflaged gecko (Saltuarius eximius) that sports an odd, broad, flattened
tail that resembles a leaf or lichen. Living in an isolated rain forest on
Australia's Cape Melville, the approximately 4.5-inch-long (11.5 centimeters)
lizard was discovered by an expedition funded by the National Geographic
Expeditions Council.
A DROP IN THE
BUCKET
Quentin Wheeler,
president of SUNY-ESF and founding director of the International Institute for Species Exploration, says these animals represent a tiny sliver of the world's
undiscovered species. There are perhaps 12 million species of plants, animals,
and fungi—and about 50 million if you add bacteria and microbes called
archaea—of which we've discovered and described fewer than two million.
"We have not
increased our rate of species discovery and description at all since before
World War II," said Wheeler. "It's pretty much a steady state of
17,000 to 18,000 species a year. Given the technological advances in recent
decades, I find that really inexcusable. We could easily be working an order of
magnitude faster."
Even worse, he
says, human encroachment on natural habitats, deforestation, pollution, and
climate change are causing species to go extinct before we can describe them.
According to a
recent paper in Science, Earth will reach mass extinction status—defined
as the loss of 75 percent or more of plant and animal species—within 300 years
if current rates continue. The last time that happened? Sixty-five million
years ago, when the asteroid that killed the dinosaurs struck the Earth.
"Some people
say, 'Well, the Earth recovered from that one and is quite diverse and pleasant
today,'" said Wheeler. "And that's true. The problem is it took tens
of millions of years—and it wouldn't have been a very nice place to live during
those tens of millions of years."
WORLD OF WONDERS
Still, the
biodiversity that remains is often mind-boggling.
Other species on
this year's Top 10 list include a giant two-inch-long (five centimeters)
single-celled organism (protist) called an agglutinated foraminifer
(Spiculosiphon oceana), which welds its own skeleton together using organic
glue and discarded silica sponge spicules—glassy sponge-skeleton components
shaped like needles. When it's done, it looks remarkably like a carnivorous
sponge. And it behaves like a carnivorous sponge too: It impales plankton on
its pointy home and squeezes part of its body through gaps in its armor to feed
on them.
There's also a
new species of 250-micrometer-long parasitoid wasp called a fairy fly—the
sweetly named Tinkerbella nana—whose delicate wings look like eyelashes
glued to Q-tips; a hardy bacterium (Tersicoccus phoenicis) that survives
in places food is virtually nonexistent and can withstand the heat of
spacecraft clean-rooms, drying, UV light, and hydrogen peroxide treatments; a
dragon tree, Dracaena kaweesakii; and a rusty-looking fungus
(Pennicillium vanoranjei) named after the Prince of Orange of the Dutch
royal family.
Rounding out the
list is a land snail (Zospeum tholussum) that lives 3,000 feet (914
meters) down in a Croatian cave and may set a new land-creep record by moving
only a few millimeters per week. When you live in pitch-dark over half a mile
below the Earth's surface, speed doesn't seem to be of the essence.
Source:
http://www.eoearth.org/view/article/
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