Because of the obvious humanness of the Turkana Boy fossil, and the fact that H. erectus brain sizes overlap the extreme lower range
of modern human brain sizes, creationists have nowadays almost entirely abandoned the old line (popularized by Duane Gish) that Peking Man and Java Man are apes, and now generally claim that Homo erectus fossils are a variant form of modern humans (ignoring the inconvenient fact that there are many obvious differences between Homo erectus and Homo sapiens).
So although the extreme lower range
of modern human brain sizes does overlap that of Homo erectus, their skulls are very different: in H. erectus, the brain case really is smaller in relation to the rest of the skull.
The evolution
of modern human brain shape.
Under those specifications, the hypothetical human brain grew as big as ancient humans» brains are thought to have grown, and the slow growth rate matched that
of modern human brains.
Not exact matches
A
modern banana, an ant, a bumble bee, a monkey (the ones you think we came from), and the
human brain (among a million other things created) disprove the theory
of evolution in just one sentence worth
of their description.
To believe that the
human brain happened by itself (over any amount
of time)... considering the complexity
of our
brains compared to the
modern computer is a little absurd.
One could cite many possible causes:
modern biology led some to question the possibility that the
human brain could ever «contain» such an unimaginable breadth
of knowledge; or more commonly, many theologians argued that Christ's genuine humanity is somehow undermined if he shares in the Father's own self - knowledge.
Modern psychosomatic medicine has made some progress in analyzing along these lines; for example, it seems quite possible that the emotional tone
of my soul may directly alter the patterns
of physical feeling in my stomach.4 Still, we should not suppose too quickly that the aims
of a
human personality have any very effective direct influence on the molecules
of body cells, other than those in the
brain.
It is for this reason that utopian thinking led some
of its
modern promoters, such as Arthur Koestler and Carl Sagan, to propose ways
of «improving»
human beings by biological manipulation such as surgical removal
of certain centers in the
brain or by genetic engineering to remove «bad» genes.
To test this, Shelby Putt, an anthropologist at the Stone Age Institute and Indiana University, compared the
brains of modern people making Oldowan and Acheulean tools in a study published earlier this year in Nature
Human Behavior.
Hardy's team highlights the following observations to build a case for dietary carbohydrate being essential for the evolution
of modern big -
brained humans:
Its big
brain and tall body are all similar to those
of modern humans.
For comparison,
modern humans have a
brain capacity
of around 1,350 cubic centimeters.
First
of all,
humans, don't get your hopes up to high: a
modern chess AI could beat your
brains out (and Deep Blue's, too).
If so, it would mean that, rather than being an 18,000 - year - old representative
of a new species, the hobbit was just a
modern human with a growth disorder that left it with a
brain the size
of a grapefruit, among other odd traits, which is what critics have argued all along.
But within days skeptics emerged, countering that the tiny remains instead belonged to a small - bodied population
of modern humans and that LB1 — with her tiny
brain and other odd features — was a diseased member
of the group.
Through trial and error and ingenuity,
modern artists have discovered ways
of tapping into idiosyncratic aspects
of the
brain's primitive perceptual grammar, producing the equivalent for the
human brain of what the striped stick is for the chick's
brain.
There seemed to be two periods
of interbreeding between
modern and ancient
humans (such as Neanderthals, perhaps Denisovans, and other large -
brained hominid cousins).
As well, the
brain of El Sidrón J1 was roughly 87.5 %
of the size
of an average adult Neandertal
brain upon death, whereas
modern humans tend to have on average 95 %
of adult
brain weight by that same age.
A new analysis
of a well - preserved skeleton
of a Neandertal child reveals that the ancient
human species may have had an extended period
of brain growth compared to
modern humans.
Scientists are particularly curious about differences in
brain size, since adult Neandertals tend to have a cranial capacity
of about 1,500 cubic centimeters and
modern day
humans have a cranial capacity
of about 1,350 cubic centimeters.
This was a presentation given by Tom Schoenemann
of the University
of Michigan at Dearborn, and what he did was to survey cranial capacity and body weight data, so
brain size and body weight data for a bunch
of modern humans and also [a] fossil one, and he plotted all
of this on a graph and he determined that the
brain size
of the Flores hominid relative to her body size more closely approximates that what you see in the Australopithecines, which are much older, you know.
Over millions
of years, the result
of this game
of survival
of the fittest was the appearance
of big -
brained, peculiarly intelligent
modern humans.
The
brain of H. habilis was considerably smaller than that
of modern humans, but larger than that
of Australopithecus, the family widely viewed as its ancestors.
The first members
of our genus that looked like us, H. erectus stood about as tall as
modern humans, with
brains that weighed around 900 grams.
A furious debate ensued: the fossil discoverers classify the meter - tall hominin as part
of a separate species that lived as recently as 12,000 years ago; others maintain it was a
modern human who had microcephaly, in which the
brain fails to reach normal size.
Researchers knew that Neanderthal
brains reached full size between the ages
of 6 and 8 years and that they were about 10 percent larger than the
brains of modern humans.
By now, the fossils have made it clear that these pioneers were startlingly primitive, with small bodies about 1.5 meters tall, simple tools, and
brains one - third to one - half the size
of modern humans».
The remarkably complete «Skull 5» features a big jaw, big teeth and overhanging eyebrows — but the
brain was just one - third the size
of a
modern human's.
It turns out that their
brains developed somewhat differently from those
of modern humans, however, both in size and in speed
of growth.
These tall, relatively large -
brained ancestors
of modern humans arose about 1.9 million years ago and soon afterward invented a sophisticated new tool, the hand ax.
The finding, reported here today at the annual meeting
of the American Association for the Advancement
of Science, publisher
of ScienceNOW, suggests to the researcher that
modern behaviors such as dolling up with jewelry may have originated from a need to communicate rather than a fundamental change in the
human brain.
Most
modern studies
of bipolar disorder have concentrated on the
brain's cortex, the largest part
of the
brain in
humans, associated with higher - level thought and action.
Recent studies
of human fossils suggest the
brain shrank more quickly than the body in near -
modern times.
We use those obvious questions as stepping - stones toward what we hope is a much more nuanced view
of the
modern neuroscientific understanding
of how the three or so pounds
of brain in your head can give rise to the complexities
of the
human experience.
The new MRI evidence points to a a gene variant shared by
modern - day
humans and Neanderthals that is likely involved in development
of the
brain's visual system.
Rather than inheriting big
brains from a common ancestor, Neandertals and
modern humans each developed that trait on their own, perhaps favored by changes in climate, environment, or tool use experienced separately by the two species «more than half a million years
of separate evolution,» writes Jean - Jacques Hublin, a paleoanthropologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, in a commentary in Science.
Using CT scans
of ancient and
modern human skulls, the researchers created digital
brain reconstructions, based on the shape
of the inner surface
of each skull's braincase.
«It's been proposed that Neanderthals depended on visual - spatial abilities and toolmaking, for survival, more so than on the social affiliation and group activities that typify the success
of modern humans — and that Neanderthal
brains evolved to preferentially support these visuospatial functions,» Berman explained.
The finding that an important
brain gene has continued to evolve adaptively in anatomically
modern humans suggests the ongoing evolutionary plasticity
of the
human brain.
Images
of it hint at interesting features close to one
brain region associated with speech in
modern humans, she says.
If
brain size had anything to do with innovation and creativity, some scientists expected to see a link between the so - called Mind's Big Bang (the emergence
of bone tools and cave paintings that occurred between 50,000 and 70,000 years ago) and the emergence
of modern - size
human brains.
But Vinge laid down the
modern version, which was that consciousness — there is nothing mystical about it — that consciousness as it occurs in
human brains is something that is the result
of physical processes and biological processes and chemical processes and because
of that it will be reproducible.
These highly successful early bipedal hominins such as Ardipithecus ramidus or Australopithecus afarensis, were nevertheless relatively small -
brained, with a cranial capacity
of about 450cm3 compared with
modern humans with over 1,500 cm3.
On the negative side, the researchers found that many
of the genes whose activity is unique to
modern humans are linked to diseases like Alzheimer's disease, autism and schizophrenia, suggesting that these recent changes in our
brain may underlie some
of the psychiatric disorders that are so common in
humans today.
By using highly advanced
brain imaging technology to observe
modern humans crafting ancient tools, an Indiana University neuroarchaeologist has found evidence that
human - like ways
of thinking may have emerged as early as 1.8 million years ago.
In terms
of features from the late archaic / early
modern humans found throughout the Old World, the researchers observed the fossils as having a large size that fitted a large
brain, and cranial vaults that were lightly built and had modest brow ridges.
Two views
of a composite reconstruction
of the Homo sapiens fossils are based on tomographic scans
of multiple original fossils; they reveal a face that would be nearly identical to that
of modern humans, but a less - evolved
brain shape.
But despite some
modern traits, it has a number
of australopithecine features, and a
brain size
of only about 750 cc (compared to the
modern human average
of at least 1350 cc).
«Anatomically, the Neandertals are quite similar to ourselves, having a skeletal arrangement identical to ours,
brains as large as ours, and - to the best
of our knowledge - the capability to perform any act normally within the ability
of a
modern human.»