Map of life expectancy at birth from Global Education Project.

Monday, February 22, 2021

More on Science

I alluded previously to much of what I'm going to say here but I want to unpack it a bit. As I noted, at the time Benjamin Franklin experimented with electricity, it wasn't obvious that his investigations had any economic value. And indeed they didn't for another hundred years or so. But as people came to understand more about electricity, it completely transformed the world. Einstein's general theory of relativity had no evident value either, until the Global Positioning System came along, and now it's essential. Same with quantum theory - it's essential to the engineering of the device you are reading this on, among other technological achievements.


Same with the life sciences. When Leeuwenhoek looked through the microscope and saw his "animalcules," it wasn't obvious that the discovery was important, but now we know it is absolutely essential to public health, medicine, and how the world works including agriculture. By studying non-human animals we gain insight into our own nature. And science works by putting together findings and methods from disparate sources. 


Chimpanzees (not monkeys) are our closest living relatives. Well, about as close as bonobos anyway. Studying their behavior has taught us a lot about ourselves. One of their behaviors that was mysterious for a long time is that they like to throw things. Like Clayton Kershaw - well, not quite like him, but like me anyway - they can throw pretty hard and pretty accurately. No other primate does this. Sometimes they might do it to ward off a rival or protect themselves, but they often do it for no obvious reason. The reason chimp in the zoo throw feces, by the way, is because they usually don't have anything else handy. In the wild, they throw rocks and vegetation.

 

Some scientists studied this, partly with funding from NIH, and they published their results in the Philosophical Transactions of the Royal Society.  Pretty prestigious! That's where Leeuwenhoek published his observations, in 1677, and that's where Franklin published his kite experiment. It turns out to be interesting for several reasons. Here's the abstract:


It has been hypothesized that neurological adaptations associated with evolutionary selection for throwing may have served as a precursor for the emergence of language and speech in early hominins. Although there are reports of individual differences in aimed throwing in wild and captive apes, to date there has not been a single study that has examined the potential neuroanatomical correlates of this very unique tool-use behaviour in non-human primates. In this study, we examined whether differences in the ratio of white (WM) to grey matter (GM) were evident in the homologue to Broca's area as well as the motor-hand area of the precentral gyrus (termed the KNOB) in chimpanzees that reliably throw compared with those that do not. We found that the proportion of WM in Broca's homologue and the KNOB was significantly higher in subjects that reliably throw compared with those that do not. We further found that asymmetries in WM within both brain regions were larger in the hemisphere contralateral to the chimpanzee's preferred throwing hand. We also found that chimpanzees that reliably throw show significantly better communication abilities than chimpanzees that do not. These results suggest that chimpanzees that have learned to throw have developed greater cortical connectivity between primary motor cortex and the Broca's area homologue. It is suggested that during hominin evolution, after the split between the lines leading to chimpanzees and humans, there was intense selection on increased motor skills associated with throwing and that this potentially formed the foundation for left hemisphere specialization associated with language and speech found in modern humans.

 

There's a good deal more to it than that. For example:

 

Throwing, as a form of social tool use, is also unique because it likely develops in captive chimpanzees (and possibly wild apes) by way of very different processes and reinforcement contingencies compared with other forms of tool use, notably those described for the purposes of food extraction. . . . In contrast, the rewards associated with throwing are quite different because they are not nutritive in form. Throwing in wild chimpanzees is seldom, if ever, observed for the purposes of obtaining food, but rather is almost always directed towards other chimpanzees or humans. In captivity, it is difficult to imagine that human caretakers would overtly reward a chimpanzee with food immediately after they had just been soiled with faeces by the very same ape. In short, what appears to be the main reward for throwing is the simple ability to control or manipulate the behaviour of the targeted individual (ape or human).

And: 

 

Some have suggested that the increased selection for neural synchrony of rapid muscular sequencing routines associated with actions such as throwing are similar to the motor programming demands of language and speech, and therefore engage similar neural systems, notably Broca's area [24]. Moreover, because the left hemisphere is dominant for language, some have argued that the foundations for left hemisphere lateralization in language may have evolved from an initial preadaptation for right-handedness in throwing

 

There is a good deal more and it's quite fascinating. This is in a themed issue, "'From action to language: comparative perspectives on primate tool use, gesture and the evolution of human language." That the neural correlates of overhand throwing and language are closely related may seem counterintuitive, but it is a meaningful piece in the puzzle of neuroscience. As a practical matter, it may contribute to rehabilitation from brain injury and to our understanding of human development. Children enjoy all sorts of games involving throwing, including simply throwing rocks at targets or playing catch, and those are part of our early socialization, while their language skills are also developing. 

 

The point I want to make here is that the essential spirit of science is exploration and discovery for its own sake. We never know what practical benefits may shake out in the end, but it would be a huge mistake to limit scientists to endeavors with an obvious practical end. If we had done that historically, we would be as ignorant as we were 1,000 years ago. 



1 comment:

Don Quixote said...

I support true scientific inquiry, such as the study you've written about here.

Republicans support it, too--just for themselves, and no one else. For others, they want the government to "stay out of people's lives." But not for Shitler, who received monoclonal antibodies when he was tanking from Covid-19. Would Josh Hawley refuse cancer treatment? Only for "those people."

I think it's time US senators and congress reps receive the same health care as the rest of us.

The irony is rich: Some people in Michigan are receiving vaccinations at DeVos Place in Grand Rapids, MI. Yep, the same family of the woman who wanted to help destroy education.