We can learn a lot from 'Pongo' family<\/p>\n
Just as Asia's only great ape faces its greatest crisis,
\nscientists have released important new findings on the species.<\/p>\n
The latest research has found that the major differences in
\nappearance, behavior and genetics of orangutans in Sumatra and
\nBorneo warrant their reclassification as separate species -- the
\nBornean Pongo pygmaeus and the Sumatran Pongo abellii.<\/p>\n
Previously they were regarded as subspecies of the same
\nspecies.<\/p>\n
"Sumatran orangutan females give birth, on average, once every
\nnine years, while females in eastern Borneo average six years,
\nwith western Borneo females somewhere in between," said Carel van
\nSchaik, a professor of biological anthropology at Duke University
\nin the United States.<\/p>\n
"The shorter birth-interval for eastern Borneo is probably as
\na result of them having a slightly higher adult mortality. This
\nis probably due to the fact that orangutans in eastern Borneo
\nhave harsher climatic conditions to deal with. They have less
\nfruit and long periods of time when there are only leaves to
\neat," said Professor van Schaik.<\/p>\n
"If you go into the leaf-eating business, there are risks that
\nyou'll poison yourself," he added<\/p>\n
As well, scientists now regard Bornean orangutans as forming
\nthree separate subspecies, with distinct differences even within
\nsubspecies in different areas.<\/p>\n
"Within Borneo there are all these big rivers which separate
\nthem and they are clearly separate populations. They are
\nbiologically different, and what is more for me as an
\nanthropologist, is that we see all kinds of cultural differences
\nbetween orangutan populations."<\/p>\n
One example is how different populations perform their "kiss-
\nsqueak", the distress signal orangutans send to each other or to
\na predator.<\/p>\n
"As researchers recording orangutan behavior in the forest
\ncanopy, we used to just write down 'kiss-squeak', but we've just
\nrecently realized that in some places they kiss-squeak on the
\nflat of their hand, to enhance the sound, while in other places
\nthey shape their hand like a trumpet and turn it as they squeak.<\/p>\n
"In other places they kiss on leaves, but sometimes it's a
\nsingle leaf and sometimes they strip a whole bunch of leaves.
\nThen they stretch out their hand and rain the leaves down on you.<\/p>\n
It enhances the message that this animal is not a happy puppy,
\nright?"<\/p>\n
"Now this shows that the animals are incredibly 'copying-
\noriented'. Like us, they have role models that they emulate and
\nthey say 'OK this is how one does it here, I'll do it that way
\ntoo.'"<\/p>\n
Professor van Schaik believes studying such behavioral
\ndifferences will help us understand the evolution of human
\nculture and intelligence.<\/p>\n
"We are just another great ape, and yet we are so vastly
\ndifferent from the others. What caused that? The best way to look
\nat that, because our ancestors are gone of course, is to look at
\nall the variability among the great apes we still have.<\/p>\n
"What causes that variability, what brings all that out in the
\ngreat apes? (If we answer those questions) maybe we can
\nextrapolate from that toward humans. We might learn a lot about
\nour own history by studying the orangutans, but we need a lot of
\npopulations. You can't study that in one population. So even if
\nby some miracle one population is saved in perpetuity, we will
\nstill lose that opportunity to study our own past."<\/p>\n
Professor van Schaik says the orangutan faces what he calls,
\n'the redwood problem', based on President Reagan's comment 'If
\nyou've seen one redwood you've seen them all.'<\/p>\n
"If you apply that to the orangutans you think - I've looked
\nat one orangutan, now I know them all. It turns out you don't
\nknow them at all because orangutans show incredible variability
\nwithin and across their subspecies," said Professor van Schaik.<\/p>\n
But these new classifications could soon be meaningless as
\nspecies and subspecies alike near extinction. There are fewer
\nthan seven thousand Sumatran orangutan left, and the subspecies
\nin East Kalimantan, the black orangutan, has only a few
\nfragmented populations remaining.<\/p>\n
"Just imagine that you have to tell children," said Professor
\nvan Schaik, "'this is the orangutan, it used to live in these
\nforests. People sort of figured out what they did but they didn't
\nquite learn everything there was to learn before they went
\nextinct. And now you'll have to live in a world without them.'"<\/p>\n
"If we let a species become extinct that's so intelligent, so
\ngenetically close to us, so charismatic, then what do the
\nbuffaloes have to hope for, what do the birds have to hope for?"
\nsaid Dr Willie Smits, Chairman of Borneo Orangutan Survival (BOS)
\nFoundation.<\/p>\n
"And eventually that whole net is going to collapse - what do
\nwe humans have to hope for ourselves? So the orangutan are a big
\nwarning flag for what is so us to come."<\/p>\n
-- Jacqueline Mackenzie<\/p>", "url": "https:\/\/jawawa.id\/newsitem\/we-can-learn-a-lot-from-pongo-family-1447898762", "image": "" }, "sponsor": "Okusi Associates", "sponsor_url": "https:\/\/okusiassociates.com" }