The newly found teeth look more
human than chimp, the researchers say.
On the ground, moving from fruit tree to fruit tree, bonobos often stand and walk on two legs — behavior that makes them seem more like
humans than chimps.
They found that, just as the gorilla is more distantly related to
humans than the chimp is, the same is true of their respective microbiomes.
One known difference is in a region called Broca's area, which is also involved in speech and is larger in
humans than chimps.
Not exact matches
A new study has theorized that
human beings are more closely related to orangutans
than chimps.
Those who are offended by the claim that horses or
chimps or whales (OFD; also see OOTM 13, WM 49) deserve more respect
than the fetus in the early stages of pregnancy usually resort to a type of question - begging which Peter Singer calls «speciesism»: the
human fetus in the early stages of pregnancy deserves moral respect just because it is
human.
But, since we
humans have been mixing with one another for a tens of thousands of years, since it is more likely that any random black person on earth has more in common genetically with a random white person
than another random black person (due to probability, because there are so many black people from differing genetic subgroups), and since
humans share 96 % of our genetic makeup with
chimps, the concept of «race» is really, scientifically, just a fiction best left to ignorant crazies like the Aryan nation.
The frontal brain grooves on a H. naledi endocast, like those in modern
humans, lie farther back
than the grooves seen in the
chimp MRI scan, Hurst contends.
Because the spinal cord entered the skull at the bottom rather
than at the back, as it does for
chimps, Dart believed the individual had walked upright — until then, considered an exclusively
human trait.
Given that the
human volunteers in Kret's study were more responsive
than the
chimps to changes in pupil size, it might be that the whites of our eyes evolved to help us subconsciously spot those changes more readily, says Harrison.
The found that chimpanzees on a whole were less violent
than humans, which researchers believe suggests that
humans developed more severe forms of warfare compared to
chimps.
This kind of prosocial behavior, a form of altruism that seeks to benefit others and promote cooperation, has now been found in
chimps, the species that Darwin did more
than any other
human to connect us with.
In the deep forest, the
chimps are fearless, «approaching us in the trees to get a better look,» Hicks says, rather
than fleeing at the sight of
humans, as
chimps in other regions tend to do.
«Many traits that distinguish
humans from
chimps are believed to have evolved more recently
than the
human — Neanderthal split,» observes biostatistician Katherine S. Pollard of the Gladstone Institutes at the University of California, San Francisco.
And 40 genes involved in these nine schizophrenia - related pathways also differed much more between
chimps and
humans than genes associated with the other 12.
When they measured the concentrations in the same area in
chimp brains, the team found that the differences between
chimps and normal
humans were much greater for those nine
than for the 12 metabolites not implicated in schizophrenia, suggesting that energy pathways implicated in schizophrenia were also altered by
human evolution, the team reports this week in Genome Biology.
Although
chimps» bodies are lean compared with those of
humans, new measurements show that these apes burn calories more slowly
than we do.
In 2012, his team reported that
humans had a different form of these fatty acid genes
than did
chimps or other ancient
human species, one that made them more efficient at processing the fatty acids from plants.
This meant that
humans burned over 27 % more energy per day on average
than chimps.
In each of the
chimp,
human, and gorilla, more
than 500 genes have been evolving faster
than expected, suggesting that they have changed in a way that confers some advantage.
The Neanderthal DNA was more similar to
human than to
chimp.
Because
human T cells don't have as many of these brakes, our cells are a hundred times more aggressive
than those of
chimps when faced with drugs like TGN1412, which work by triggering the immune system.
After taking body size into account, they found that
humans averaged about 400 more calories per day
than chimps and bonobos — 635 calories more
than gorillas and 820 calories more
than orangutans.
And the variation in skull size and facial shape is no greater
than in other species, including both modern
humans or
chimps, says Ponce de León — especially when the growth of the jaw and face over a lifetime are considered.
To this slim, ponytailed young woman,
chimps looked more clever, more scary, and often more
human than anyone had ever suspected.
A multitude of factors help makes the
human brain superior to the
chimps», but new research indicates that looser genetic control of brain development in
humans allows us to learn and adapt to our environment with more flexibility
than our primate cousins.
Two
chimp brothers would have more similar sulci
than two
human brothers, for instance.
Indeed, a close look at the
chimp genome reveals an important lesson in how genes and evolution work, and it suggests that
chimps and
humans are a lot more similar
than even a neurobiologist might think.
On the reasonable assumption that
chimp and
human laughter are homologous rather
than independently evolved traits, laughter must be at least 5 million to 7 million years old.
Mature dogs look like wolf pups, and
humans look more like
chimp infants
than chimp adults, researchers noted at the meeting.
As a result, the embryos carrying
human HARE5 have brains that are 12 % larger
than the brains of mice carrying the
chimp version of the enhancer.
The blue stains in these developing mice embryos show that the
human DNA inserted into the rodents turns on sooner and is more widespread (right)
than the
chimp version of the same DNA, promoting a bigger brain.
Once the ancestors of
humans split from the ancestor of bonobos and
chimps more
than 4 million years ago, the common ancestor of bonobos and
chimps retained this diversity until their population completely split into two groups 1 million years ago.
As researchers study the genome in more depth, they hope to find the genetic differences that make bonobos more playful
than chimps, for example, or
humans more cerebral.
The researchers also found that the ancestors of
humans split from the ancestor of bonobos and
chimps more
than 4 million years ago, not more
than 5 million years ago as originally reported.
Chimps spend at least 6 hours a day chewing, he notes,
humans, less
than 1.
In 2002 he reported that a gene known as FOXP2, which plays a role in language acquisition, produces a subtly different protein in
humans than in
chimps.
Members of a tiny tribe in the Amazon jungle that has no words for numbers beyond two can't conceptualize numbers any better
than chimps or
human infants do, a new study has found.
Based on their research from the Chorora, Kadabba and Ardi finds, the team says the common ancestor of
chimps and
humans lived earlier
than had been evidenced by genetic and molecular studies, which placed the split about 5 million years ago.
Thirty years ago, geneticist Mary - Claire King and biochemist Allan Wilson proposed that changes in how genes are regulated, rather
than in the proteins they code for, could explain important differences between
chimps and
humans (Science, 11 April 1975, p. 107).
But in the brain, the team detected much more gene expression in
humans than in
chimps, whereas gene expression in the brains of
chimps and the other primates was about the same.
They found that the chimpanzee Y chromosome has lost lots of genes that are present in
humans, which suggests the
human Y resembles that of the common ancestor more
than does the
chimp's Y. Chimpanzees only have two - thirds of the genes present in the
human MSY.
The sequencing of the
human genome (ScienceNOW, 14 April 2003:) gave scientists major new insights into what makes us
human: Although we share more
than 98 % of our genetic code with the chimpanzee, natural selection has turned us into a very different animal
than the
chimps, from whom our hominid ancestors split evolutionarily some 6 million years ago (ScienceNOW, 31 August).
The team speculates that detrimental mutations have survived in
humans and
chimps because these species have had much smaller breeding populations
than rodents throughout evolution.
The mutations may also explain why some genes have much different expression levels
than would be expected between
humans and
chimps.
The researchers then determined that the stones must have been
chimp tools because of their size: a typical
human hammer stone is no longer
than 120 millimeters (less
than 5 inches) and weighs less
than 400 grams (less
than one pound).
While the specialized adaptations of our hands have long been assumed as a major evolutionary advantage, the
human hand is less developed in terms of evolution
than that of a
chimp, having changed little from the hands of the last common ancestor shared with our simian cousins millions of years ago, scientists report.
«The sequence difference is larger
than the average sequence difference between
humans and
chimps, so we estimate it occurred at least 4 million years ago,» Andersson explained.
Regulator genes help determine how other genes will express themselves, and the researchers suspected that some of these regulators might be making brain development more active in
human embryos
than in
chimps.
This allowed them to compare the level of expression of more
than 1,000 genes between
humans,
chimps, orangutans and rhesus macaques — representing about 70 million years of evolution.