Saturday, August 31, 2024

Brain Size and the Emergence of Modern Human Cognition

This essay, by Ian Tattersall, from Rethinking Human Evolution, is probably the last I'll discuss from the book. Like the other essays, it challenges conventional wisdom regarding human evolution and makes some good points.

For reasons previously explored both by this author (Tattersall 1997, 2015) and by the editor of this volume (Schwartz 2006, 2016), paleoanthropology has been mired since the mid-twentieth century in the beguiling notion that evolution in the hominid family (hominin subfamily/tribe, if you prefer; the difference is notional) has consisted essentially of the burnishing by natural selection of a central lineage that culminated in Homo sapiens. Yet accretions to the hominid fossil record over the same period have, in contrast, consistently shown that hominid phylogeny instead involved vigorous evolutionary experimentation. Over the seven-million-odd years of our family's existence, new species and lineages were regularly thrown out onto the ecological stage, to be triaged in competition with organisms both closely and distantly related. Extinction rates were high to match. Further, it is by now well established that all this took place in the context of constantly oscillating climates and habitats (deMenocal, 2011), to which steady, perfecting adaptation would not have been possible, even in principle.....the gradualist interpretive framework has tenaciously lingered, leading to the widespread application in practice of a strictly minimalist systemic approach that has often been justified by spectacularly contorted reasoning (see Spoor et al. [2007], and Lordkipanidze et al. [2014] for classic examples).

Tattersall looks closely at brain size in various hominids. The generally accepted narrative, which I've mentioned before, is that our ancestors first became bipedal due to climate change and the replacement of forest with savannah; this led to dietary changes in which meat provided a more efficient energy source, and cooperation increased, leading to language development and increased brain size. Tattersall says that, although brain size did increase generally in hominids, there is no evidence that this increase alone correlates with increased intelligence. One hypothesis is that the demands of human childrearing required higher intelligence. Tattersall adopts a different position. He thinks that the development of language in early Homo sapiens provided the main impetus. By about 100,000 years ago, humans were sufficiently adept in the use of symbolic language that they were able to manipulate symbols in their thinking processes, which roughly corresponds with what we think of as intelligence. So, Tattersall's view is that what we think of as intelligence is an unexpected byproduct of the acquisition of language. And, although brain size did initially play a role, it doesn't necessarily now. For example, the now- extinct Neanderthals had larger brains than us but apparently lacked our capacity for symbolic manipulation. Additionally, human brain size has been decreasing for tens of thousands of years. Tattersall compares this to early brute force computers (such as Deep Blue), which had to be large to solve problems, whereas recent, smaller algorithmic computers solve even harder problems more efficiently. On the whole, Tattersall's point is that the development of human cognition did not occur within a context of steady movement toward a likely end; a more accurate description is that, at any given time, nature seems to be conducting various survival experiments for which no outcome is clear. Additionally, energy usage often plays a role in evolution. Neanderthals had large bodies and brains, so they were energy-inefficient compared to humans. Strangely, we are now running into similar constraints with cryptocurrencies and AI, which are already straining our energy resources. It looks as if the evolutionary model for both animals and machines may be the movement to lower energy consumption combined with higher performance. Without the sun, we wouldn't be here.

These thoughts relate to those of other writers I've discussed. For example, Giorgio Vallortigara has shown that even chicks use basic arithmetic and geometry, but without symbols or language. This is a good example of how a cognitive function can become more useful through the use of symbolic reasoning. There is also somewhat of a connection with the work of Vinod Goel, who discusses the evolution of the human brain, which is actually a wider look than Tattersall's discussion. Tattersall is probably only talking about the prefrontal cortex, which is relatively small, and the rest of the human brain is mostly quite ancient. Looking at this only from the present, the determinists I've discussed may have some relevance, because they specifically emphasize human limitations and the variability of skills within the current population. This group includes Robert Sapolsky, Robert Plomin, David Reich and Kathryn Paige Harden. While Tattersall is apparently happy that evolution managed to allow us to be here today, he doesn't discuss the liabilities that we've inherited from our evolutionary past. Having myself observed human behavior for seventy-four years now, there is a lot not to like about it.

Monday, August 26, 2024

Human and Mammalian Evolution: Is There a Difference?

This short essay, by John de Vos and Jelle W.F. Reumer, is another from the book I'm reading. I found it interesting and will just sum it up.

From ancient times to the present, there has been a conceit regarding the place of humans in the world. De Vos and Reumer state this nicely as follows:

When God created the world, he did so in a succession of different steps. The creation of animals was one such step. The creation of mankind was another one. Ever since, mankind has been considered (i.e., has considered itself) not to be part of the animal kingdom. This notion—that Homo sapiens is a species next to, above, or outside the mammalian world—has long perverted science. Ernst Haeckel's famous "Stammbaum des Menschen/Pedigree of Man," published in 1874, shows "man" in the highest branch of the tree, above the rest of the living world, although part of the apes.

Commendably, these authors prefer to study humans as mammals, and their research shows that, in the past, environmental changes affected humans just as much as other mammals. The Pliocene period, 5.3 to 2.6 million years ago, entailed a cooling of the planet, during which forests were transformed to grassy plains in the American prairies, the Eurasian steppes and the African savannahs. Horses and antelopes evolved from smaller, shorter-legged animals to have longer legs, new dental characteristics and increased socialization. The Pliocene, with its increase in grasslands, was also the time of origin for early hominids such as Australopithecus.

Thus, both the evolution of human bipedalism and erect posture on the one hand, and of the long-legged running gait in horses on the other, are the result of Miocene-through-Pleistocene climate change in conjunction with the reduction of forest ecosystems and increase in open habitats....Humans, antelopes and horses are mammals that adapted to a new environment, and their evolution reflects their convergences.

There are also parallels between humans and other mammals seen in studies of island paleontology:

Although the mechanisms leading to observed phenomena remain unclear, these studies have given rise to what is called the "Island Rule." That is, in general, small mammals (shrews, hedgehogs, rodents, leporids) become larger when isolated on islands, and large mammals (elephantids, hippopotamids, bovids, cervids) become smaller....Although until fairly recently one might have wondered if humans would be an exception to the Island Rule, the possibility emerged with the discovery of the remains of a Late Pleistocene hominid on the Indonesian island of Flores....Claims of microcephaly notwithstanding, the specimens are more reasonably seen as evidence of island dwarfing and of a separate species.

During the Late Pleistocene, many large mammals became woolly: the woolly mammoth, woolly rhinoceros, musk ox and cave bear. At that time, the climate was cold and dry. But at the end of the Pleistocene, the climate became warmer, and most of the woolly species became extinct. As a speculative matter, the authors suggest that Homo neanderthalensis, which had evolved during the Pleistocene, may also have been "woolly," and became extinct along with the other woolly mammals.

The point of the authors is that large mammals are large mammals, and there are probably convergences when different species experience the same environmental changes. From a scientific point of view, I think this is fairly obvious – though it would be heresy to many.

Tuesday, August 20, 2024

Sex, Reproduction, and Scenarios of Human Evolution

This is a short essay by Claudine Cohen in Rethinking Human Evolution, edited by Jeffrey H. Schwartz, which is part of a series in theoretical biology. I will probably read several of the essays and comment separately on each one. I am attempting to update myself in a field that I find interesting.

In The Descent of Man, Charles Darwin speculated that in early human history mate selection was performed by females, based on the physical and social characteristics of males, and that these choices affected the characteristics of males over time. This is the same idea that I mentioned a few years ago, regarding speculation that Dutch men are the tallest in the world because Dutch women selected them, considering tall men better providers than short men. However, Darwin thought that mate selection later became a male behavior, and that women began to adorn themselves so as to make themselves more attractive to men. While Darwin admitted that sociocultural practices can affect mate selection, he thought that, after the early period, males generally tended to dominate women.

From the 1920's to the 1970's, cultural anthropologists rejected biological evolutionary models in favor of human social structures. In the mid-1970's sociobiology was popularized by E.O. Wilson and gene-maximization was popularized by Richard Dawkins. I think that Cohen may conflate Wilson's views with those of Dawkins, because they are not identical. She thinks that Dawkins's support of gene-maximization is reductionistic and provides an unsubstantiated advantage to males. Wilson's views are more concerned with group or multi-level selection, which are different things entirely. In any case, Cohen favors maintaining the importance of socio-cultural factors in human sexual behavior and she seems to dislike genetic explanations of this subject. When she wrote this essay (in about 2016), other deterministic models, such as Robert Sapolsky's, were not well known. I think that the clunky old cause-effect model of determinism, especially through genes, is giving way to a messier model such as Sapolsky's. Under that model, specific behaviors of humans do emerge causally, but we can barely comprehend how. Different sexual behavior does emerge from different social contexts, but those contexts also fit within broader deterministic models. While Cohen does seem to approve of Darwin's views, she does not focus on the central Darwinian idea that species go extinct for a wide variety of reasons: if a species goes extinct as a result of its social practices, it lacks fitness, according to Darwin, and social causes may be just as causal as the earth being struck by a large asteroid. I think that many people, even in the sciences, inject free will into their theories because it provides the feeling that we have control over our destinies – even though we don't. 

I found Cohen a bit more enlightening in other areas. The fact of concealed ovulation in humans, but not in other primates, had been a puzzle to me. Was it to conceal paternity? There is a convincingly simple hypothetical explanation for this: bipedal gate. The genital exposure of female humans is much less conspicuous than that of other primates, not attracting as much attention. So it is quite conceivable that, with the gradual development of other erogenous zones in the female body, the role of sexual signaling from the vulva gradually declined. The increasing complexity of human social structures, including the use of clothing, may also have reduced the desirability of conspicuous estrus:

In the absence of visible estrus, human sexual behavior and reproduction become disconnected (Godelier, 2004). Consequently, the uniquely human manifestations of eroticism and sexual pleasure (see Bataille 1957, 1961), coexist with, and may even replace, the physiological function of procreation (Zwang 2002).

More generally:

The acquisition of concealed ovulation has been viewed as a key event leading to the transformation of gender relationships and roles in human groups. If it was related to the acquisition of Hominin bipedal gait, its roots lie well before the origin of the genus Homo. Understanding concealed ovulation – its origin, causes, and effects – is likely fundamental to understanding human evolution and the emergence of social structure, as is reflected in its being the starting point of several scenarios of "hominization."

Another interesting area that Cohen delves into is the social and other effects of the demands of raising human babies. The workload is so high that a male partner is generally needed to at least provide food. But cooperation spills over into the surrounding group, leading to general cooperation within that group. More interestingly, humans are the only primates with menopause, and other female primates remain fertile up to their deaths. 

Whereas young female apes leave their mothers to join their male partners' territories (patrilocality), the positive role of grandmothers is favored by matrilocality, that is, the cohabitation of daughters with mothers (in contrast to cohabitation of the son's mother and his wife). In turn, this leads to a close and harmonious distribution of roles for caring and educating children. In humans, matrilocality permits a better environment for raising young children. Older women, freed of reproductive constraints, can achieve the status of a wise and dominant figure, and contribute to the welfare of their group, by virtue of the knowledge and experience they acquired over a long period of time, one that extends well beyond the cessation of fertility.

In this vein, Cohen suggests that figurines such as the Venus of Willendorf (28,000-25,000 BCE) are not symbols of fertility, but represent the importance of postmenopausal women in those societies.  



Tuesday, August 13, 2024

Diary

I've been distracted by some minor inconveniences for a few days. The remains of Hurricane Debby came through here on August 9, with wind and rain. My neighborhood was hardly affected, but the power and my internet went out. The power outage lasted only a few hours, and, since I have a generator, that wasn't a problem. But then, after Comcast informed me that the internet was back up, it actually wasn't. I contacted them, and they set an appointment on August 16 for a technician to come. I put myself on a wait list for August 11 and then August 12, and a technician arrived yesterday. He thought that the problem was my modem, though it's only a year old. I spent yesterday driving down to Rutland and back, buying and installing a new modem, identical to the old one, only to find that it also didn't work. From that point onward, I was unable to communicate with a human at Comcast. Consequently, in an effort to examine every possibility, I tried using the new modem's electric adapter, and subsequently found that it works on both the old and new modems. So, now I have two good modems. I've ordered a extra adapter for both modems and should have no modem problems for several years. I might add that cellular signals are very weak in my neighborhood; when the internet is down, I often have to drive to a location with a better cellular signal. For wireless internet I park outside the Brandon library. Without internet at home, I'm significantly cut off from the world. For me, this is yet another example of the decline in customer service in the current economic environment. Customer service is so bad now that I am hesitant to participate in many previously accessible activities, such as air travel. I haven't flown on a plane since 2016.

The cooling trend here has begun, and the hummingbirds are flying south. Yesterday, one of them scared the Comcast technician on the front porch. The atmosphere is already fall-like, and there have been some clear nights. There is a glitch with my new stargazing equipment, but I should be able to fix it eventually. The tomatoes have recovered, and there will be a lot of them soon. After the late germinations and deer attack, they're not all the same size, but they all have tomatoes growing on them: more than I can eat. The germination problem, I determined, was that I had stored the seeds in the basement, which gets humid in the summer. In the Middlebury basement there was a dehumidifier.

I'm dutifully trying to pay attention to the presidential election, but it's a bit like watching a bad soap opera rerun. I find it difficult to watch a dishonest, fat and stupid old rich guy pretend that he actually has something to offer. J.D. Vance complements him as an unscrupulous opportunist. He represents the next generation of political grifters. When I see the news media and the public taking them seriously, I start to experience violent paroxysms of cognitive dissonance. For example, we have to watch the Republicans question Tim Walz's military record and ignore the fact that Trump himself engaged in a carefully-orchestrated draft-dodging scheme during the Vietnam War. If I were an authoritarian dictator, I would deport Trump and Vance to Venezuela to spend the rest of their days with their friend, Nicolás Maduro. On the other hand, Kamala Harris is a nice change of pace, and I like Tim Walz. At the moment, they are gaining momentum and seem likely to win. Trump has very little self-discipline, and he seems to be digging his own grave. Still, the underlying problem is the idiotic voters who elected him in 2016.

I will be starting a book of essays on human evolution soon and may have something more interesting to say.

Friday, August 2, 2024

Autocracy, Inc.: The Dictators Who Want to Run the World

This is a new book by Anne Applebaum, the journalist. Politics isn't one of my favorite subjects, but global politics have become so complicated in recent years that I thought that I should get an update. Although this book is written in a journalistic style and lacks an index, Applebaum is experienced and insightful regarding the topic. The writing is a bit jerky at times, because it integrates magazine articles that were written separately. 

 Autocracies have been around for thousands of years, but there was somewhat of a lull following World War II, when world leaders founded organizations such as the UN in order to keep global order. What is confusing now is that, not only have they made a big comeback, but that there is a new ecosystem in which autocrats regularly assist each other even when they have different goals and ideologies. A good example comes from the relationship between Venezuela and Iran:

Since 2000, Iran has systematically increased its aid, first for Chávez and then Maduro. Iranians bought Venezuelan gold and sent food and gasoline in return. Iranians are believed to be advising Venezuela on repressive tactics against dissidents. Iranians helped Venezuela build a drone factory (apparently with mixed success) and have sent equipment and personnel to help repair Venezuelan oil refineries. The Venezuelans, for their part, might have helped launder money for Hezbollah, the Iran-backed terrorist group, and are believed to have provided passports for Hezbollah and Iran officials as well.

Besides Iran, Venezuela is getting help from Russia, China, Cuba and Turkey.

In the most general sense, today's autocrats don't have rigid ideologies and are tolerant of other autocrats who are willing to work with them. This sometimes means that large, well-organized countries such as Russia and China are working directly with brutal thugs who like wealth and power and don't care about their own countries at all.

The king of evil autocrats seems to be Vladimir Putin, who has spent much of his adult life working on autocratic schemes. He benefited from his familiarity with techniques employed by Stalin long ago. The Nord Stream natural gas pipeline to Germany began operation in 2011 and has provided stolen funds to Putin that are used to finance his various projects. This helped Russia become a leading kleptocracy, as Applebaum describes it. The stolen funds go to Putin's facilitators all over the world through a vast network of money laundering. Because the money is stolen, it doesn't have to be invested carefully, and it can end up in unneeded new buildings. Applebaum advocates transparency in real estate ownership, because kleptocrats currently live in unidentified homes all over the world, including the U.S. and U.K. 

Applebaum's main solution to the autocracy problem is as follows:

...the democracies of North America, Latin America, Europe, Asia, and Africa, together with the leaders of democratic opposition in Russia, China, Iran, Venezuela, Cuba, Belarus, Zimbabwe, Myanmar, and other autocratic states, should think about the struggle for freedom not as a competition with specific autocratic states, and certainly not as "war with China," but as a war against autocratic behaviors, wherever they are found: in Russia, in China, in Europe, in the United States.

Since American social media sites are hardly regulated, she also advocates legislation to correct that for the users.

Trump does come up in the book in a couple of places. For example: 

The fact that anonymous shell companies were purchasing condominiums in Trump-branded properties while Trump was president should have set off alarm bells. That it did not is evidence of how accustomed to kleptocratic corruption we have become.

My view is that, because Trump is a narcissist and isn't particularly talented, in the course of his life he has moved from one field to another, and each time he fails. He wasn't particularly successful as a real estate developer and failed as a casino operator. He also tried and failed at leveraged buyouts when they were popular. His main success was in becoming an actor specializing in characters who are great businessmen. I think that he admires autocrats because he would like that job. He would love it if everyone had to agree with him and praised him all of the time.

Overall, autocracies are a complex topic, and they are still evolving. This book provides some of the basic information that you need to know now. I would have liked to know more about Xi Jinping, because he remains somewhat of a mystery to me. Applebaum is not unrealistic about the difficulties of democratic processes, which are the main alternative, but seems less skeptical of them than I am. Because I look at humans biologically, it is obvious to me that we have gradually been creating greater and greater risks to our continued existence, and that one of these days our luck may run out.