Abram — The Arabm..an
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You and I are not plants. We are creatures; specifically, animals. But, we’re a special kind of animal — Human. Specifically, a human called homo sapiens. There were other humans such as Hominins and Neanderthals. But, they have died out. What makes Homo Sapiens so special? Mainly because we have the ability to plan. This is a big deal. At least to us. Also, because we have the ability to conceive of something as being “A big deal”. We assume that this attribute is important in the overall scheme of things. Well, perhaps it is and then again, perhaps not. Anyway, all the foregoing is called forethought. As far as we know, humans have the unique power of forethought: the ability to imagine possibilities (the future) and then to actually choose one of those possibilities. Forethought also allows humans generative and creative abilities unlike those of any other species of animal.
Evolutionary biology and scientific evidence tell us that all Homo sapiens evolved from apelike ancestors more than 6 million years ago in what is now called Africa. Information obtained from early-human fossils and archaeological remains suggests that there were 15 to 20 different species of early humans several million years before that. These species, generically called hominins, migrated into Asia around 2 million years ago, then into Europe and then to the rest of the world much later. Although different branches of humans died out, the branch leading to the modern human, Homo sapiens, survived.
Homo sapiens diverged from an early-apelike ancestor more than 100,000 years ago. The shape of the mouth and vocal tract changed, with the tongue and voice box, moving further down the throat. Most species that have existed on planet Earth are now extinct, including a number of early human species.
Homo sapiens have much in common with other mammals on Earth in terms of physiology but are most like two other living primate species in terms of genetics and morphology: the chimpanzee and bonobo. However, as much like the chimpanzee and bonobo as we are, the differences are vast.
Apart from our obvious intellectual capabilities that distinguish us as a species, humans have several unique physical, social, biological, and emotional traits. Although we don’t know precisely what is in the minds of other animals, scientists can make inferences through studies of animal behavior that inform our understanding.
One physical feature is that modern Homo sapiens are relatively hairless. Although there are other mammals that are hairless — the whale, elephant, and rhinoceros, to name a few — humans are the only primates to have mostly naked skin. Homo sapiens evolved that way because changes in the climate 200,000 years ago that demanded that they travel long distances for food and water. Homo sapiens also have an abundance of sweat glands, called eccrine glands. To make these glands more efficient, human bodies had to lose their hair to better dissipate heat. This enabled them to obtain the food they needed to nourish their bodies and brains, while keeping them at the right temperature and allowing them to grow.
Another significant traits that make Homo sapiens unique preceded and possibly led to the development of other notable characteristics: bipedalism — that is, using only two legs for walking. This trait emerged not only in Homo sapiens but in other humans millions of years ago, early in their evolutionary development and gave humans the advantage of being able to hold, carry, pick up, throw, touch, and see from a higher vantage point, with vision as the dominant sense. As human legs evolved to become longer about 1.6 million years ago and humans became more upright, they were able to travel great distances as well, expending relatively little energy in the process.
Big brain Homo Sapiens
But, the human feature that is most extraordinary is the brain. We are talking about the human called Homo Sapiens. The relative size, scale, and capacity of the Homo sapiens’ brain are greater than those of any other species. [ We assume that this is of significance]. The size of the human brain relative to the total weight of the average homo sapiens is 1-to-50. Most other mammals have a ratio of only 1-to-180.
The homo sapiens brain is three times the size of a gorilla brain. Although it is the same size as a chimpanzee brain at birth, the Homo sapiens brain grows more during the lifespan of a Homo sapiens to become three times the size of the chimpanzee brain. In particular, the prefrontal cortex grows to encompass 33 percent of the human brain compared to 17 percent of the chimpanzee brain. The adult Homo sapiens brain has about 86 billion neurons, of which the cerebral cortex comprises 16 billion. In comparison, the chimpanzee cerebral cortex has 6.2 billion neurons. It is theorized that childhood is much longer for Homo sapiens, with offspring remaining with their parents for a longer period of time because it takes longer for the larger, more complex Homo sapiens brain to fully develop. Studies suggest that the brain is not fully developed until the ages of 25 to 30.
The brain of homo sapiens and the activity of its countless neurons and synaptic possibilities contribute to mind. The mind is different from the brain: The brain is the tangible, visible part of the physical body whereas the mind consists of the intangible realm of thoughts, feelings, beliefs, and consciousness.
In his book “The Gap: The Science of What Separates Us From Other Animals,” Thomas Suddendorf suggests:
“Mind is a tricky concept. I think I know what a mind is because I have one — or because I am one. You might feel the same. But the minds of others are not directly observable. We assume that others have minds somewhat like ours — filled with beliefs and desires — but we can only infer those mental states. We cannot see, feel, or touch them. We largely rely on language to inform each other about what is on our minds.”