Here is a little video of the Cuttlefish and its flamboyent colours
This species is well worth highlighting for its beauty and rarity. They are highly prized on a divers must see list. Distribution, central indo region, southern Philippines to Northern Australia.
Once discovered, instead of leaving the area they will usually stay in the same place for some months so revisiting is possible. Rather than seeing this species swimming they prefer to walk the substrate on two front tentacles and two skin flaps located on the underbelly, this is clearly illustrated within our field guide images. Look for the sandy appearance on the "walking" front tentacles and the underbelly skin flaps, this is where the creature makes contact with the substrate.
They are active in daylight hours and their coloration is generally brown to match the substrate (darker in Indonesia due to darker sand).
They show flamboyant displays of red, yellow, white and pink chevrons that move up and down their bodies pulsating in a mesmerizing rhythm. Like other cuttlefish they produce instant colour changes.
Their elaborate coloration may indicate a poisonous bite like its cousin the Blue Ringed Octopus.
Their maximum size is approx. 10cm. Imperial Partner Shrimps live a symbiotic relationship with many creatures including cuttlefish for more information please visit our Marine Biology Crustacean page.
University of Florida College of Pharmacy researchers have
discovered a marine compound off the coast of Key Largo that inhibits
cancer cell growth in laboratory tests, a finding they hope will fuel
the development of new drugs to better battle the disease.
The
UF-patented compound, largazole, is derived from cyanobacteria that
grow on coral reefs. Researchers, who described results from early
studies today (Aug. 7) at an international natural products scientific
meeting in Athens, Greece, say it is one of the most promising they’ve
found since the college’s marine natural products laboratory was
established three years ago.
An initial set of papers in the Journal of the American Chemical Society
also has garnered the attention of other scientists, and the lab is
racing to complete additional research. The molecule’s natural chemical
structure and ability to inhibit cancer cell growth were first
described in the journal in February and the laboratory synthesis and
description of the molecular basis for its anticancer activity appeared
July 2.
"It’s exciting because we’ve found a compound in
nature that may one day surpass a currently marketed drug or could
become the structural template for rationally designed drugs with
improved selectivity," said Hendrik Luesch, Ph.D., an assistant
professor in UF’s department of medicinal chemistry and the study’s
principal investigator.
Largazole, discovered and named by
Luesch for its Florida location and structural features, seeks out a
family of enzymes called histone deacetylase, or HDAC. Overactivity of
certain HDACs has been associated with several cancers such as prostate
and colon tumors, and inhibiting HDACs can activate tumor-suppressor
genes that have been silenced in these cancers.
Although
scientists have been probing the depths of the ocean for marine
products since the early 1960s, many pharmaceutical companies lost
interest before researchers could deliver useful compounds because
natural products were considered too costly and time-consuming to
research and develop.
Many common medications, from pain
relievers to cholesterol-reducing statins, stem from natural products
that grow on the earth, but there is literally an ocean of compounds
yet to be discovered in our seas. Only 14 marine natural products
developed are in clinical trials today, Luesch said, and one drug
recently approved in Europe is the first-ever marine-derived anticancer
agent.
"Marine study is in its infancy," said William Fenical,
Ph.D., a distinguished professor of oceanography and pharmaceutical
sciences at the University of California, San Diego. "The ocean is a
genetically distinct environment and the single, most diverse source of
new molecules to be discovered."
The history of pharmacy
traces its roots back thousands of years to plants growing on Earth’s
continents, used by ancient civilizations for medicinal purposes,
Fenical added. Yet only in the past 30 years have scientists begun to
explore the organisms in Earth’s oceans, he said. Fewer than 30 labs
exist worldwide and research dollars have only become available in the
past 15 years.
HDACs are already targeted by a drug approved
for cutaneous T-cell lymphoma manufactured by the global pharmaceutical
company Merck & Co. Inc. However, UF’s compound does not inhibit
all HDACs equally, meaning a largazole-based drug might result in
improved therapies and fewer side effects, Luesch said.
Since
2006, Luesch and his team of researchers have screened cyanobacteria
provided by collaborator Valerie Paul, Ph.D., head scientist at the
Smithsonian Marine Station in Fort Pierce. They check the samples for
toxic activity against cancer cells and last year encountered one
exceptionally potent extract — the one that ultimately yielded
largazole.
To conduct further biological testing on the
compound, Luesch and his team have been collaborating with Jiyong Hong,
an assistant professor in the department of chemistry at Duke
University, to replicate its natural structure and its actions in the
laboratory.
Luesch said that within the next few months he plans to study whether largazole reduces or prevents tumor growth in mice.
Luesch has several other antitumor natural products from Atlantic and Pacific cyanobacteria in the pipeline.
"We
have only scratched the surface of the chemical diversity in the
ocean," Luesch said. "The opportunities for marine drug discovery are
spectacular."
A little eight-legged pickpocket that darts around acacia trees could be the first known vegetarian
spider.
Bagheera kiplingi belongs among the big-eyed, athletic predators in the family of jumping spiders and gets its name from a panther in a Rudyard Kipling story. Yet a population of these spiders in Mexico mostly eats bits of the acacia trees, says Christopher Meehan of Villanova University in Pennsylvania.
A few other spider species do taste vegetable matter now and then, says Yael Lubin of Ben-Gurion University in Sede Boqer, Israel. Male crab spiders that spend their brief mating-oriented adult lives sitting on flowers will sip nectar for a little energy boost. And some baby spiders eat spores that have stuck to a web. But on hearing about spiders specializing in stealing vegetarian food, “I was absolutely floored,” Lubin says.
These arachnid herbivores are no wimps. “The tree is full of biting, vicious ant guards,” Meehan said during the 12th International Behavioral Ecology Congress meeting August 9 through 15 at Cornell University. The little spider spends its life dodging patrols of ants and stealing their (vegetarian) lunches.
Acacia trees and their resident ants have become a textbook example of a mutually beneficial partnership. Tree thorns grow swollen bases the right size to shelter ants. Glands at the base of the leaves ooze nectar, far from flowers but just at the spot to offer refreshment for ants. Acacia leaflet tips sprout nubbins of protein and fat suitable for ant snacks.
Certain ant species take full advantage of these comforts and defend their home trees against all comers. In the course of their vigilance, the ants get rid of caterpillars and other invaders that might chew on the tree.
Meehan says the spiders manage to dodge the ants, perching on leaf tips and nesting in mature leaves, which aren’t as heavily patrolled as other tree parts.
Ecologists have studied the partnership for years, but “people who look at ant acacias — they look at the ants,” Lubin says. “It took the eyes of a student naturalist to see this.”
That fresh observer was Meehan, who, along with his Villanova colleague Robert Curry, noticed the spiders dining on the leafy snacks of acacias in Mexico. In videos of 140 spider meals, the researchers counted 136 acacia protein-fat snacks with a few nectar sips. On four occasions the spiders did turn to meat as they tugged away ant larvae from a passing nursemaid and ate the youngsters.
In Costa Rica, the spiders also steal ant food, though to a lesser extent, according to observations from Eric Olson of Brandeis University. He independently discovered the spiders eating tree snacks in Costa Rica in 2001 and is working with the Villanova team on a report on the species.
Those meat moments don’t happen often, according to studies done in collaboration with Matt Reudink and others of Queen’s University in Kingston, Canada. The team checked spider tissue for the heavier form of nitrogen, N15, which becomes more concentrated as animals eat animals that have eaten other animals.
That carnivore signal does not show up in the acacia-tree spiders, which carry a relatively light concentration of N15, one that is typical of plant-eaters, according to the team’s data. He also found that the concentration of the heavier form of carbon, C13, also looks typical for a vegetarian.
Long a problem in the western U.S., the New Zealand mud snail
currently inhabits four of the five Great Lakes and is spreading into
rivers and tributaries, according to a Penn State team of researchers.
These tiny creatures out-compete native snails and insects, but are not
good fish food replacements for the native species.
"These snails have an operculum, a door that closes the
shell," says Edward P. Levri, associate professor of biology at Penn
State’s Altoona Campus. "They can be out of the water for longer than
other snails and when fed to fish, they are not digested and sometimes
come out alive. This has a potential to alter the salmon and trout
fisheries because they alter the food chain."
The New Zealand mud snail grows to a maximum of a quarter of
an inch and is more normally a sixteenth to an eighth of an inch in
length. The hard shell is capable of sealing off the soft animal from
outside influences. In New Zealand, the snails reproduce asexually,
resulting in identical clones, or sexually. However, in invaded areas,
asexual cloning is the only mode of reproduction.
This mud snail spread to England as early as 1850 and Europe
in the late 1800s. It is found in Japan, but when the snail arrived
there is unknown. The first mud snail found in the U.S. was in 1987 in
the Snake River, Idaho, but the species did not appear in the east
until 1991 in Lake Ontario. The western and eastern U.S. populations
are separate episodes of introduction, because they represent different
clones; in each case, only one snail needed to be introduced to begin
the invasion. The snails in the Great Lakes region appear to be the
same as one clone found in Europe.
"In the western U.S., this species is of special concern
largely because of their ability to modify ecosystems," Levri told
attendees today (Aug. at the Ecological Society of America’s annual
meeting in Milwaukee.
The snails in western streams alter the nitrogen and carbon
cycling. They are primarily grazers and detritus eaters with very wide
food preferences. In some places in streams in Yellowstone National
Park, they reach population densities of 323 individuals per square
inch. Levri, working with undergraduates Warren J. Jacoby, Shane J.
Lunen, Ashley A. Kelly and Thomas A. Ladson, found that densities in
the Great Lakes are not anywhere near that in the West.
"In our most recent survey, we were lucky if we found a few
hundred per square meter," says Levri. "In Lake Erie they are not very
abundant, but it is unclear what they are doing 100 feet below the
surface."
In New Zealand, the mud snails are not a problem because of
native trematodes — flukes — that infect the snails and controls
their population and reproduction. Some people have suggested that
those who want to control the snail introduce this trematode to the
U.S. to control the snails.
"There are two problems with introducing these trematodes,"
says Levri. "The first is that any introduction of a nonnative species
can cause worse problems than they were expected to cure. The second is
that these flukes have a multiple-host life cycle, infecting ducks that
are apparently not affected before infecting the snails. This might
work in the west where the snails are in shallow water, but no duck is
going to dive 100 feet to get snails."
Levri and his team found that in Lake Ontario, the densities
of the snails peak between 50 and 82 feet and they were rarely found in
water less than 16 feet.
"What we can do is limit their expansion," says Levri. "That
means that recreational water users must be very careful moving from
one place to another. We advise anglers to freeze waders and fishing
gear, or use Formula 409 or something like that to kill the snails."
He notes that signs are beginning to mark areas in New York where the snail is found to warn people to clean their gear.
The
Penn State researcher warns that the snails are difficult to control,
noting "I have frozen them for 12 hours at a time and about 50 percent
of them survive."
Research looks at how intergroup harmony in the US changed as a result of the September 11, 2001, terrorist attacks
Foreign
threats to the United States can encourage tolerance for diversity
domestically and a corresponding intolerance for diversity
internationally, according to a study by University of British Columbia
(UBC) and Stanford University researchers published this week in Journal of Personality and Social Psychology.
On
September 11, 2001, Paul Davies was a post-doctoral fellow at Stanford
University working on the psychology of intergroup relations. As
military jets escorted passenger airliners from the skies in the hours
after terrorist attacks in New York, Washington and in the air over
Pennsylvania, Davies realized that all around him the interactions
between people had shifted dramatically.
"The world changed
instantaneously," he says. "Foreigner became synonymous with enemy.
There was all this animosity directed towards any foreigner, and at the
same time there was an extraordinary outpouring of brotherly love
within America. We had this paradox that 9/11 led to intergroup harmony
inside the United States while leading to intergroup conflict outside
the United States."
Davies decided to look more closely at
what was happening. Within a few months, he and co-investigators Claude
Steele and Hazel Rose Markus from Stanford University had a research
program ready to go — examining the relationship between foreign
threats, national identity and citizens’ endorsement of models for both
foreign and domestic intergroup relations.
"To the best of our
knowledge, this line of research is the first to document these
relationships," says Davies, who is now a professor of psychology at UBC’s Okanagan campus.
"Our initial studies, conducted during the week of the six-month
anniversary of 9/11, had Americans read a U.S. senator’s policy on
intergroup relations. During this period of national challenge,
Americans endorsed multiculturalism more as a domestic policy and
assimilation more as a foreign policy."
Davies notes that a
foreign policy of assimilation presumes that your nation’s values,
principles, and practices are a model for all foreign cultures to
emulate. That’s in stark contrast to multiculturalism, which strives to
have a reciprocal relationship with other cultures and embraces
diversity as a source of strength.
In subsequent research,
American participants were exposed to a United Nations report that
either challenged or supported U.S. global status. Americans who read
that foreigners were threatening the dominant status of the U.S. once
again revealed a strong preference for assimilation (i.e. promoting the
U.S. as a model for foreign countries to emulate) as a foreign policy,
but Americans who read that foreigners were supporting the dominant
status of the U.S. no longer revealed this preference.
"Most
recently, we discovered that Americans primed with 9/11 — a foreign
threat — revealed higher levels of national identity than those primed
with the Columbine massacre — a domestic threat," says Davies. He
points out that a heightened level of national identity predicted
support for multiculturalism as a domestic policy and support for
assimilation as a foreign policy.
"During a period of national
challenge, embracing one’s national identity can be highly adaptive,"
Davies says. "The healing power of embracing one’s national identity
was obvious among the 78 percent of Americans who indicated, in 2002,
that 9/11 and its aftermath has changed America for the better. Perhaps
the greatest tragedy of all is that calamity can unite people in a way
that shared humanity cannot."
A study reported in the August 8th issue of the journal Cell,
a Cell Press publication, reveals the complete mitochondrial genome of
a 38,000-year-old Neandertal. The findings open a window into the
Neandertals’ past and helps answer lingering questions about our
relationship to them.
" For the first time, we’ve built a
sequence from ancient DNA that is essentially without error," said
Richard Green of Max-Planck Institute for Evolutionary Anthropology in
Germany.
The key is that they sequenced the Neandertal
mitochondria—powerhouses of the cell with their own DNA including 13
protein-coding genes—nearly 35 times over. That impressive coverage
allowed them to sort out those differences between the Neandertal and
human genomes resulting from damage to the degraded DNA extracted from
ancient bone versus true evolutionary changes.
Although it is
well established that Neandertals are the hominid form most closely
related to present-day humans, their exact relationship to us remains
uncertain, according to the researchers. The notion that Neandertals
and humans may have "mixed" is still a matter of some controversy.
Analysis of the new sequence confirms that the mitochondria of
Neandertal’s falls outside the variation found in humans today,
offering no evidence of admixture between the two lineages although it
remains a possibility. It also shows that the last common ancestor of
Neandertals and humans lived about 660,000 years ago, give or take
140,000 years.
Of the 13 proteins encoded in the
mitochondrial DNA, they found that one, known as subunit 2 of
cytochrome c oxidase of the mitochondrial electron transport chain or
COX2, had experienced a surprising number of amino acid substitutions
in humans since the separation from Neandertals. While the finding is
intriguing, Green said, it’s not yet clear what it means.
" We
also wanted to know about the history of the Neandertal’s themselves,"
said Jeffrey Good, also of the Max-Planck Institute. For instance, the
new sequence information revealed that the Neandertal’s have fewer
evolutionary changes overall, but a greater number that alter the amino
acid building blocks of proteins. One straightforward interpretation of
that finding is that the Neandertal’s had a smaller population size
than humans do, which makes natural selection less effective in
removing mutations.
That notion is consistent with arguments
made by other scientists based upon the geological record, said
co-author Johannes Krause. "Most argue there were a few thousand
Neandertals that roamed over Europe 40,000 years ago." That smaller
population might have been the result of the smaller size of Europe
compared to Africa. The Neandertals also would have had to deal with
repeated glaciations, he noted.
" It’s still an open question
for the future whether this small group of Neandertals was a general
feature, or was this caused by some bottleneck in their population size
that happened late in the game?" Green said. Ultimately, they hope to
get DNA sequence information for Neandertals that predated the Ice Age,
to look for a signature that their populations had been larger in the
past.
Technically, the Neandertal mitochondrial genome
presented in the new study is a useful forerunner for the sequencing of
the complete Neandertal nuclear genome, the researchers said, a feat
that their team already has well underway.
Carriers of a common gene variation startled more dramatically in response to unpleasant pictures
Inborn differences may help explain why trauma gives some people bad
memories and others the nightmare of post-traumatic stress. Scientists
in Germany and the United States have reported evidence linking genes
to anxious behavior. The findings appear in the August issue of
Behavioral Neuroscience, published by the American Psychological
Association.
By showing that people who carry a common
variation of a gene that regulates the neurotransmitter dopamine have
an exaggerated "startle" reflex when viewing unpleasant pictures, the
researchers offer a biochemical explanation for why some people find it
harder to regulate emotional arousal. Their sensitivity may, in
combination with other hereditary and environmental factors, make them
more prone to anxiety disorders.
Researchers including
Martin Reuter, PhD, of the University of Bonn, Germany, recruited 96
women averaging 22 years old from the Giessen Gene Brain Behavior
Project, which investigates biomolecular causes of individual
differences in behavior.
The researchers first determined
which participants carried which variations (alleles) of the COMT gene,
which encodes an enzyme that breaks down dopamine, weakening its
signal. (COMT stands for a catabolic enzyme named
catechol-O-methyltransferase.) Scientists call its two alleles Val158
and Met158. Depending on ethnicity, more or less half the population
carries one copy of each. The rest of the population is roughly divided
between carrying two copies of Val158 and two copies of Met158.
Using
a well-validated psychophysiological measure, the researchers next
measured the intensity of each participant’s startle response by
attaching electrodes to the eye muscles that, upon emotional arousal,
contract and cause a blink. Participants then viewed pictures that were
emotionally pleasant (such as animals or babies), neutral (such as a
power outlet or hairdryer), or aversive (such as weapons or injured
victims at a crime scene) — 12 pictures of each type for six seconds
each. A loud, 35-millisecond white noise, called a startle probe,
sounded at random while they watched. When participants blinked,
showing the startle response, a bioamplifier took readings from the
electrodes and sent the information to a computer for analysis.
People
carrying two copies of the Met158 allele of the COMT gene showed a
significantly stronger startle reflex in the unpleasant-picture
condition than did carriers of either two copies of Val158 allele or
one copy of each. The two-Met carriers also disclosed greater anxiety
on a standard personality test.
This finding confirms that
specific variations in the gene that regulates dopamine signaling may
play a role in negative emotionality. The authors speculated that the
Met158 allele may raise levels of circulating dopamine in the brain’s
limbic system, a set of structures that support (among other things)
memory, emotional arousal and attention. The researchers said that more
dopamine in the prefrontal cortex could result in an "inflexible
attentional focus" on unpleasant stimuli, meaning that Met158 carriers
can’t tear themselves away from something that’s arousing — even if
it’s bad.
The Met158 allele was created by a relatively
recent mutation and only in the evolution of human beings. Other
primate species such as chimpanzees carry only the Val/Val genotype.
Co-author Christian Montag, Dipl. Psych., observes that for humans,
wariness may have been adaptive. He points out, "It was an advantage to
be more anxious in a dangerous environment."
A single gene
variation, says Montag, can explain only a small portion of variation
in anxious behavior – otherwise, in theory, up to half the population
could be anxious.
"This single gene variation is potentially
only one of many factors influencing such a complex trait as anxiety,"
he says. "Still, to identify the first candidates for genes associated
with an anxiety-prone personality is a step in the right direction."
Although
a great deal more research is needed, Montag says that if this line of
research bears fruit, one day "it might be possible to prescribe the
right dose of the right drug, relative to genetic makeup, to treat
anxiety disorders."
A COMMON parasite can increase a women’s
attractiveness to the opposite sex but also make men more stupid, an
Australian researcher says.
About 40 per cent of the world’s population is infected with Toxoplasma gondii, including about eight million Australians.
Human infection generally occurs when people eat raw or undercooked
meat that has cysts containing the parasite, or accidentally ingest
some of the parasite’s eggs excreted by an infected cat.
The parasite is known to be dangerous to pregnant women as it can cause
disability or abortion of the unborn child, and can also kill people
whose immune systems are weakened.
Until recently it was thought to be an insignificant disease in healthy
people, Sydney University of Technology infectious disease researcher
Nicky Boulter said, but new research has revealed its mind-altering
properties.
"Interestingly, the effect of infection is different between men and women,” Dr Boulter writes in the latest issue of Australasian Science magazine.
"Infected men have lower IQs, achieve a lower level of education and
have shorter attention spans. They are also more likely to break rules
and take risks, be more independent, more anti-social, suspicious,
jealous and morose, and are deemed less attractive to women.
"On the other hand, infected women tend to be more outgoing, friendly,
more promiscuous, and are considered more attractive to men compared
with non-infected controls.
"In short, it can make men behave like alley cats and women behave like sex kittens”.
Dr Boulter said the recent Czech Republic research was not conclusive,
but was backed up by animal studies that found infection also changes
the behaviour of mice.
The mice were more likely to take risks that increased their chance of
being eaten by cats, which would allow the parasite to continue its
life cycle.
Rodents treated with drugs that killed the parasites reversed their behaviour, Dr Boulter said.
Another study showed people who were infected but not showing symptoms
were 2.7 times more likely than uninfected people to be involved in a
car accident as a driver or pedestrian, while other research has linked
the parasite to higher incidences of schizophrenia.
"The increasing body of evidence connecting Toxoplasma infection with
changes in personality and mental state, combined with the extremely
high incidence of human infection in both developing and developed
countries, warrants increased government funding and research, in
particular to find safe and effective treatments or vaccines,” Dr
Boulter said.
Deep in the hinterlands of the Republic of the Congo lies a secret ape paradise that is home to 125,000 western lowland gorillas, researchers announced today.
The findings, if confirmed, would more than double the world’s estimated population of gorillas.
Western lowland gorillas are a subspecies classified as critically endangered by the International Union for Conservation of Nature (IUCN).
Their numbers have been devastated in recent years by illegal hunting for bush meat and the spread of the Ebola virus. Just last year scientists projected the animals’ population could fall as low as 50,000 by 2011.
Now those predictions may have to be dramatically reworked to incorporate findings released today by the Wildlife Conservation Society (WCS).
A first ever ape census in northern Congo found 73,000 of the gorillas in that country’s Ntokou-Pikounda region and 52,000 more in the Ndoki-Likouala area.
The Ndoki population includes an obscure group of nearly 6,000 gorillas living in close quarters in isolated swamps near Lac Télé.
"We knew there were apes there, we just had no idea how many," said WCS’s Emma Stokes, one of the lead researchers in the two-year project.
The gorillas have thrived thanks to their remoteness from human settlements, food-rich habitats, and two decades of conservation efforts in one of the world’s poorest countries, Stokes said.
Shy, But Plentiful
Lowland gorillas are more common than their mountain cousins. The animals are found in tropical forests and swamps in Angola, Cameroon, the Central African Republic, Congo, the Democratic Republic of the Congo, Equatorial Guinea, and Gabon.
Each group of lowland gorillas has a range of about 7.7 square miles
(20 square kilometers), and the animals build the nests to sleep in
each night before moving on in the morning.
The census work involved crossing hundreds of miles to count
nests, then loading data into a mathematical model that estimated the
number of gorillas living within a defined area.
In the 17,400-square-mile (28,000-square-kilometer)
Ndoki-Likouala region, for example, the nest census found an estimated
population density of 1.65 gorillas per square kilometer (equal to
about 0.3 square mile).
This means that about 46,200 western lowland gorillas likely
live in the area, which runs west of the Sangha River to the border of
the Central African Republic.
An additional 6,000 gorillas reside in the region’s 646-square-mile
(1,040-square-kilometer) Batanga swamps. These wetlands, which are
inaccessible to humans for more than half the year, house an estimated
five to six apes per square kilometer.
"That’s the highest density I’ve seen," Stokes said, adding
that the data suggest Ndoki-Likouala is the subspecies’ "largest
remaining stronghold."
The discovery "shows that conservation in the Republic of Congo is working," said WCS president Steven Sanderson.
Almost half the surveyed area lies within officially protected
zones or inside timber concessions where logging companies have banned
transport of protected animals and weapons on their roads.
Researchers hope the latest census will encourage the
government of Congo to establish a new national park in the
Ntokou-Pikounda region.
The census was presented today at the International Primatological
Society conference in Edinburgh, Scotland, and some of the data will
appear in an upcoming issue of the conservation journal Oryx.
Perils of Counting Apes
Several experts greeted the survey findings with a mix of excitement and caution.
"If these new gorilla census figures are confirmed by further surveys,
it would be the most exciting ape conservation news in years," said
Craig Stanford of the Jane Goodall Research Center at the University of
Southern California.
"Nest census data are notorious for varying from one method to
the next, however, and I think we should be cautious before assuming
the world’s known gorilla population has just doubled."
Nesting data were among the factors used in a 2007 IUCN
population assessment that placed the western lowland gorilla on the
organization’s Red List of Threatened Species.
IUCN estimated the gorillas had declined by more than 60 percent over
the past 25 years, and its scientists projected the apes’ population
could fall to 50,000 as the deadly Ebola virus penetrated deeper into
their habitat.
That report came with a caveat about the reliability of nest counts:
"Technical problems with the conversion of ape nest density to
estimates of gorilla density preclude a rigorous estimate of range-wide
gorilla abundance."
Peter Walsh of the Max Planck Institute for Evolutionary
Anthropology in Leipzig, Germany, led the 2007 IUCN assessment. He
repeated those concerns when he learned of WCS’s findings in northern
Congo.
"It is not that I think that the numbers are necessarily too high,"
Walsh said. "It is just that I do not trust the assumptions made by the
estimation models that are being used."
Nature’s Secrets
John Oates, professor emeritus of anthropology at Hunter College
in New York, noted that "what does seem clear is that there are still
plenty of western gorillas in northern Congo."
He remains cautious, however, about whether the new research should signal a change in status for the great apes.
In addition to habitat loss and hunting, in recent years Ebola
has ravaged gorilla habitats bordering the Ntokou-Pikounda survey area,
killing 60 percent of the apes in nearby Odzala National Park.
While WCS’s Stokes said her survey found "no evidence of Ebola
in Ntokou-Pikounda, our general philosophy is Ebola can hit anywhere,
anytime."
And with a 90 percent mortality rate among infected gorillas,
Stokes thinks the animals deserve all the protection they can get.
In general, the WCS findings demonstrate that our intensely observed
planet still has its biological secrets, added Richard Bergl, curator
of research at the North Carolina Zoo.
"It is extraordinary that in this day and age," he said, "there
could be a population of a hundred thousand or more gorillas that were
essentially unknown to science."
at the Ecological Society of America’s annual
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