http://www.iht.com/articles/2006/08/30/healthscience/snmanatee.php
By Erica Goode The New York Times
August 30, 2006
It is a good thing the manatee has thick skin. To the dolphins, the whales
and the sea otters go the admiring oohs and ahs, the cries of, "How sleek!"
"How beautiful!" The manatee, sluggish, squinty-eyed and bewhiskered, is
more likely to have its rotund bulk compared to "a sweet potato" and its
homely, almost fetal looks deemed "prehistoric."
Cleverness is unhesitatingly ascribed to the dolphin. But the manatee is not
seen leaping through hoops or performing somersaults on command, and even
scientists have suspected it may not be the smartest mammal in the sea.
Yet the conception of the simple sea cow is being turned on its head by the
recent work of Roger Reep, a neuroscientist at the University of Florida in
Gainesville, and a small group of other manatee researchers, including
Gordon Bauer, a professor of psychology at New College of Florida, and David
Mann, a biologist at the University of South Florida.
In studies over the past decade, they have shown that the endangered Florida
manatee (Trichechus manatus latirostris) is as unusual in its physiology,
sensory capabilities and brain organization as in its external appearance.
Far from being slow learners, manatees are as adept at experimental tasks as
dolphins, though they are slower-moving and, having no taste for fish, more
difficult to motivate. They have a highly developed sense of touch, mediated
by thick hairs called vibrissae that adorn not just the face, as in other
mammals, but the entire body, according to the researchers' recent work.
And where earlier scientists saw in the manatee's brain the evidence of
deficient intelligence, Reep sees evolution's shaping of an animal perfectly
adapted to its environment.
Reep is a co-author, with Robert Bonde, a biologist with the U.S. Geological
Survey, of a recently published book, "The Florida Manatee: Biology and
Conservation" (University Press of Florida). He argues that the small size
of the manatee brain may have little or nothing to do with its intelligence.
Brain size has been linked by some biologists with the elaborateness of the
survival strategies an animal must develop to find food and avoid predators.
Manatees have the lowest brain-to- body ratio of any mammal. But they are
aquatic herbivores, subsisting on sea grass and other vegetation. With the
exception of powerboats piloted by speed-happy Floridians, which kill about
80 manatees a year and maim dozens more, they have no predators.
"Manatees don't eat anybody, and they're not eaten by anybody," Reep said.
Reep suspects that rather than the manatee's brain being unusually small for
its body, the situation is the other way around: that its body, for sound
evolutionary reasons, has grown unusually large in proportion to its brain.
A large body makes it easier to keep warm in the water - essential for a
mammal like the manatee, with a glacially slow metabolism. It also provides
room for the large digestive system necessary to process giant quantities of
low-protein, low-calorie food. A manatee must consume 10 percent of its body
weight - from 800 to 1,200 pounds, or about 360 to 545 kilograms - a day.
The smooth surface of the manatee's brain - it generally has only one main
vertical fissure and no surface ridges to speak of - is more puzzling, Reep
said. The brains of virtually every mammal bigger than a small rodent show
some degree of folding. And scientists have generally taken the human
cortex, a study in ridges and crevasses, as a model of higher-order mental
process.
But Reep added that scientists still know almost nothing about what drives
the development of brain formation. Evolutionary lineage appears to have an
influence. The brains of primates tend to have different patterns of
convolution than those of carnivores, for example. And mechanical factors
like brain size and the denseness of neural tissue in the cortex may play a
role.
In any case, Reep said, brain convolution "doesn't seem to be correlated
with the capacity to do things."
Intelligence - in animals or in humans - is hard to define, much less
compare between species, Reep said. Is the intelligence of a gifted concert
pianist the same as that of a math whiz? Is a lion's cunning the same as the
cleverness of a Norwegian rat? The manatee is good at what it needs to be
good at.
It is a good thing the manatee has thick skin. To the dolphins, the whales
and the sea otters go the admiring oohs and ahs, the cries of, "How sleek!"
"How beautiful!" The manatee, sluggish, squinty-eyed and bewhiskered, is
more likely to have its rotund bulk compared to "a sweet potato" and its
homely, almost fetal looks deemed "prehistoric."
Cleverness is unhesitatingly ascribed to the dolphin. But the manatee is not
seen leaping through hoops or performing somersaults on command, and even
scientists have suspected it may not be the smartest mammal in the sea.
Yet the conception of the simple sea cow is being turned on its head by the
recent work of Roger Reep, a neuroscientist at the University of Florida in
Gainesville, and a small group of other manatee researchers, including
Gordon Bauer, a professor of psychology at New College of Florida, and David
Mann, a biologist at the University of South Florida.
In studies over the past decade, they have shown that the endangered Florida
manatee (Trichechus manatus latirostris) is as unusual in its physiology,
sensory capabilities and brain organization as in its external appearance.
Far from being slow learners, manatees are as adept at experimental tasks as
dolphins, though they are slower-moving and, having no taste for fish, more
difficult to motivate. They have a highly developed sense of touch, mediated
by thick hairs called vibrissae that adorn not just the face, as in other
mammals, but the entire body, according to the researchers' recent work.
And where earlier scientists saw in the manatee's brain the evidence of
deficient intelligence, Reep sees evolution's shaping of an animal perfectly
adapted to its environment.
Reep is a co-author, with Robert Bonde, a biologist with the U.S. Geological
Survey, of a recently published book, "The Florida Manatee: Biology and
Conservation" (University Press of Florida). He argues that the small size
of the manatee brain may have little or nothing to do with its intelligence.
Brain size has been linked by some biologists with the elaborateness of the
survival strategies an animal must develop to find food and avoid predators.
Manatees have the lowest brain-to- body ratio of any mammal. But they are
aquatic herbivores, subsisting on sea grass and other vegetation. With the
exception of powerboats piloted by speed-happy Floridians, which kill about
80 manatees a year and maim dozens more, they have no predators.
"Manatees don't eat anybody, and they're not eaten by anybody," Reep said.
Reep suspects that rather than the manatee's brain being unusually small for
its body, the situation is the other way around: that its body, for sound
evolutionary reasons, has grown unusually large in proportion to its brain.
A large body makes it easier to keep warm in the water - essential for a
mammal like the manatee, with a glacially slow metabolism. It also provides
room for the large digestive system necessary to process giant quantities of
low-protein, low-calorie food. A manatee must consume 10 percent of its body
weight - from 800 to 1,200 pounds, or about 360 to 545 kilograms - a day.
The smooth surface of the manatee's brain - it generally has only one main
vertical fissure and no surface ridges to speak of - is more puzzling, Reep
said. The brains of virtually every mammal bigger than a small rodent show
some degree of folding. And scientists have generally taken the human
cortex, a study in ridges and crevasses, as a model of higher-order mental
process.
But Reep added that scientists still know almost nothing about what drives
the development of brain formation. Evolutionary lineage appears to have an
influence. The brains of primates tend to have different patterns of
convolution than those of carnivores, for example. And mechanical factors
like brain size and the denseness of neural tissue in the cortex may play a
role.
In any case, Reep said, brain convolution "doesn't seem to be correlated
with the capacity to do things."
Intelligence - in animals or in humans - is hard to define, much less
compare between species, Reep said. Is the intelligence of a gifted concert
pianist the same as that of a math whiz? Is a lion's cunning the same as the
cleverness of a Norwegian rat? The manatee is good at what it needs to be
good at.
It is a good thing the manatee has thick skin. To the dolphins, the whales
and the sea otters go the admiring oohs and ahs, the cries of, "How sleek!"
"How beautiful!" The manatee, sluggish, squinty-eyed and bewhiskered, is
more likely to have its rotund bulk compared to "a sweet potato" and its
homely, almost fetal looks deemed "prehistoric."
Cleverness is unhesitatingly ascribed to the dolphin. But the manatee is not
seen leaping through hoops or performing somersaults on command, and even
scientists have suspected it may not be the smartest mammal in the sea.
Yet the conception of the simple sea cow is being turned on its head by the
recent work of Roger Reep, a neuroscientist at the University of Florida in
Gainesville, and a small group of other manatee researchers, including
Gordon Bauer, a professor of psychology at New College of Florida, and David
Mann, a biologist at the University of South Florida.
In studies over the past decade, they have shown that the endangered Florida
manatee (Trichechus manatus latirostris) is as unusual in its physiology,
sensory capabilities and brain organization as in its external appearance.
Far from being slow learners, manatees are as adept at experimental tasks as
dolphins, though they are slower-moving and, having no taste for fish, more
difficult to motivate. They have a highly developed sense of touch, mediated
by thick hairs called vibrissae that adorn not just the face, as in other
mammals, but the entire body, according to the researchers' recent work.
And where earlier scientists saw in the manatee's brain the evidence of
deficient intelligence, Reep sees evolution's shaping of an animal perfectly
adapted to its environment.
Reep is a co-author, with Robert Bonde, a biologist with the U.S. Geological
Survey, of a recently published book, "The Florida Manatee: Biology and
Conservation" (University Press of Florida). He argues that the small size
of the manatee brain may have little or nothing to do with its intelligence.
Brain size has been linked by some biologists with the elaborateness of the
survival strategies an animal must develop to find food and avoid predators.
Manatees have the lowest brain-to- body ratio of any mammal. But they are
aquatic herbivores, subsisting on sea grass and other vegetation. With the
exception of powerboats piloted by speed-happy Floridians, which kill about
80 manatees a year and maim dozens more, they have no predators.
"Manatees don't eat anybody, and they're not eaten by anybody," Reep said.
Reep suspects that rather than the manatee's brain being unusually small for
its body, the situation is the other way around: that its body, for sound
evolutionary reasons, has grown unusually large in proportion to its brain.
A large body makes it easier to keep warm in the water - essential for a
mammal like the manatee, with a glacially slow metabolism. It also provides
room for the large digestive system necessary to process giant quantities of
low-protein, low-calorie food. A manatee must consume 10 percent of its body
weight - from 800 to 1,200 pounds, or about 360 to 545 kilograms - a day.
The smooth surface of the manatee's brain - it generally has only one main
vertical fissure and no surface ridges to speak of - is more puzzling, Reep
said. The brains of virtually every mammal bigger than a small rodent show
some degree of folding. And scientists have generally taken the human
cortex, a study in ridges and crevasses, as a model of higher-order mental
process.
But Reep added that scientists still know almost nothing about what drives
the development of brain formation. Evolutionary lineage appears to have an
influence. The brains of primates tend to have different patterns of
convolution than those of carnivores, for example. And mechanical factors
like brain size and the denseness of neural tissue in the cortex may play a
role.
In any case, Reep said, brain convolution "doesn't seem to be correlated
with the capacity to do things."
Intelligence - in animals or in humans - is hard to define, much less
compare between species, Reep said. Is the intelligence of a gifted concert
pianist the same as that of a math whiz? Is a lion's cunning the same as the
cleverness of a Norwegian rat? The manatee is good at what it needs to be
good at.
It is a good thing the manatee has thick skin. To the dolphins, the whales
and the sea otters go the admiring oohs and ahs, the cries of, "How sleek!"
"How beautiful!" The manatee, sluggish, squinty-eyed and bewhiskered, is
more likely to have its rotund bulk compared to "a sweet potato" and its
homely, almost fetal looks deemed "prehistoric."
Cleverness is unhesitatingly ascribed to the dolphin. But the manatee is not
seen leaping through hoops or performing somersaults on command, and even
scientists have suspected it may not be the smartest mammal in the sea.
Yet the conception of the simple sea cow is being turned on its head by the
recent work of Roger Reep, a neuroscientist at the University of Florida in
Gainesville, and a small group of other manatee researchers, including
Gordon Bauer, a professor of psychology at New College of Florida, and David
Mann, a biologist at the University of South Florida.
In studies over the past decade, they have shown that the endangered Florida
manatee (Trichechus manatus latirostris) is as unusual in its physiology,
sensory capabilities and brain organization as in its external appearance.
Far from being slow learners, manatees are as adept at experimental tasks as
dolphins, though they are slower-moving and, having no taste for fish, more
difficult to motivate. They have a highly developed sense of touch, mediated
by thick hairs called vibrissae that adorn not just the face, as in other
mammals, but the entire body, according to the researchers' recent work.
And where earlier scientists saw in the manatee's brain the evidence of
deficient intelligence, Reep sees evolution's shaping of an animal perfectly
adapted to its environment.
Reep is a co-author, with Robert Bonde, a biologist with the U.S. Geological
Survey, of a recently published book, "The Florida Manatee: Biology and
Conservation" (University Press of Florida). He argues that the small size
of the manatee brain may have little or nothing to do with its intelligence.
Brain size has been linked by some biologists with the elaborateness of the
survival strategies an animal must develop to find food and avoid predators.
Manatees have the lowest brain-to- body ratio of any mammal. But they are
aquatic herbivores, subsisting on sea grass and other vegetation. With the
exception of powerboats piloted by speed-happy Floridians, which kill about
80 manatees a year and maim dozens more, they have no predators.
"Manatees don't eat anybody, and they're not eaten by anybody," Reep said.
Reep suspects that rather than the manatee's brain being unusually small for
its body, the situation is the other way around: that its body, for sound
evolutionary reasons, has grown unusually large in proportion to its brain.
A large body makes it easier to keep warm in the water - essential for a
mammal like the manatee, with a glacially slow metabolism. It also provides
room for the large digestive system necessary to process giant quantities of
low-protein, low-calorie food. A manatee must consume 10 percent of its body
weight - from 800 to 1,200 pounds, or about 360 to 545 kilograms - a day.
The smooth surface of the manatee's brain - it generally has only one main
vertical fissure and no surface ridges to speak of - is more puzzling, Reep
said. The brains of virtually every mammal bigger than a small rodent show
some degree of folding. And scientists have generally taken the human
cortex, a study in ridges and crevasses, as a model of higher-order mental
process.
But Reep added that scientists still know almost nothing about what drives
the development of brain formation. Evolutionary lineage appears to have an
influence. The brains of primates tend to have different patterns of
convolution than those of carnivores, for example. And mechanical factors
like brain size and the denseness of neural tissue in the cortex may play a
role.
In any case, Reep said, brain convolution "doesn't seem to be correlated
with the capacity to do things."
Intelligence - in animals or in humans - is hard to define, much less
compare between species, Reep said. Is the intelligence of a gifted concert
pianist the same as that of a math whiz? Is a lion's cunning the same as the
cleverness of a Norwegian rat? The manatee is good at what it needs to be
good at.
_________
http://www.animalsinthewild.org
"In a world older and more complete than ours, animals move finished and
complete, gifted with extensions of the senses we have lost or never
attained, living by voices we shall never hear. They are not underlings;
they are other nations, caught with ourselves in the net of life and time,
fellow prisoners of the splendor and travail of the earth."
Henry Beston
