Transitional Forms

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The vaunted trend to increasing complexity in the history of life, for example, only records the small and extending tail of an increasingly right-skewed distribution through time––but with a strong a persistent bacterial mode that has never altered during life’s entire 3.5 billion year history, leaving this planet now, as always, in the Age of Bacteria. This extending right tail may record little more than the constraint of life’s origin right next to the lower bound of preservable complexity in the fossil record. Only one direction––towards greater complexity––remained open to “invasion,” and a small number of species dribble in that direction through time, thus extending the right tail of the skewed distribution. But no evidence now exists to support an argument that higher complexity should be construed as a “good thing in general” (in adaptive terms, or otherwise), either at the organismal or species level. In fact, the few studies based on patterns of speciation in clades where the founding members lie far from any upper or lower structural boundary, and therefore impose no constraint upon either decreasing or increasing complexity, show no trend at all towards increasing complexity. Approximately equal numbers of species arise with less complex and with more complex phenotypes than their ancestor.

Stephen Jay Gould, The Structure of Evolutionary Theory (p. 730)

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In an experiment study Melis et al. presented pairs of chimpanzees with out-of-reach food that could be obtained only if both partners pulled simultaneously on the two ends of a rope connected to a platform. When there were two piles of food, one in front of each individual, the pairs were often successful. However, when there was only one pile of food in the middle of the platform, pulling it in typically resulted in the dominant individual monopolizing all the food. This naturally demotivated the subordinate for future collaborative efforts, so cooperation fell apart over trials. In stark contrast, in a study designed by Warneken et al. to be as comparable as possible to this one, three-year-old children were not bothered at all by the food being in a single pile in the middle of the board; they collaborated successfully over many trials no matter how the food was laid out.

Tomasello, M. (2016). A natural history of human morality. Harvard University Press.

Discussing

Melis, A. P., Hare, B., & Tomasello, M. (2006). Chimpanzees recruit the best collaborators. Science, 311(5765), 1297-1300.

and

Warneken, F., Lohse, K., Melis, A. P., & Tomasello, M. (2011). Young children share the spoils after collaboration. Psychological science, 22(2), 267-273.

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As an analogy, imagine a group of people individually trying to understand the function of a knife blade. One person tests its ability to cut peaches.  Upon finding that the blade cuts through peach flesh but not the pit, he or she concludes that the knife is specialized for peach flesh removal. Another person might test its ability to screw various types of screws; finding that the knife blade works well to screw flathead and Phillips screws, but not Allen screws, he or she might conclude that it is specialized for a subset of screwing functions. Although each of these is a valid description of the functions that the knife performs, neither seems to be an accurate description of the fundamental function of a knife blade, such as “cutting or manipulating objects depending on their hardness.

On the epistemic challenge of the current paradigm of brain-area function studies. 

Poldrack, Russell A. "Mapping mental function to brain structure: how can cognitive neuroimaging succeed?." Perspectives on Psychological Science 5.6 (2010): 753-761.

Quoted in Anderson’s After Phrenology

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Michael Hammer - Interbreeding events out of Africa - Interbreeding with Archaic Humans in Africa

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Chris Stringer - Interbreeding events in Africa - Fossil Record of Anatomically Modern Humans

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Schweber documents numerous sources in Darwin's wide readings for this central theme of political economy. In May 1840, for example, Darwin encountered the following passages in J.R. McCulloch's Principles of Political Economy:

“Every individual is constantly exerting himself to find out the most advantageous methods of employing his capital and labor. It is true, that it is his own advantage, and not that of society, which he has in view; but a society being nothing more than a collection of individuals, it is plain that each, in steadily pursuing his own aggrandisement, is following that precise line of conduct which is most for the public advantage. The true line of policy is to leave individuals to pursue their own interests in their own way, and never to lose sight of the maxim pas trop gouverner. It is by this spontaneous and unconstrained... effort of individuals to improve their conditions... and by them only, that nations become rich and powerful.”

The theory of natural selection lifts this entire explanatory structure, virgo intacta, and then applies the same causal scheme to nature-- a tough customer who can bear the hecatomb of deaths required to produce the best polity as an epiphenomenon. Individual organisms engaged in the 'struggle for existence' act as the analog of firms in competition. Reproductive success becomes the analog of profit--for, even more than in human economies, you truly cannot take it with you in nature.

Stephen Jay Gould, The Structure of Evolutionary Theory

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" A big, short-armed animal probably wasn’t flying, so what was it doing with its wings? We don’t know for sure."

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ORGANIC LIFE beneath the shoreless waves

Was born and nurs'd in Ocean's pearly caves; 

First forms minute, unseen by spheric glass, 

Move on the mud, or pierce the watery mass; 

These, as successive generations bloom 

New powers acquire, and larger limbs assume; 

Whence countless groups of vegetation spring, 

And breathing realms of fin, and feet, and wing.

Erasmus Darwin, Temple of Nature, 1803

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Morality wasn’t supposed to be like this. Most of the effective altruists I met were nonrealist utilitarians. They don’t believe in some objective moral law imposed by an outside Power. They just think that we should pursue our own human-parochial moral values effectively. If there was ever a recipe for a safe and milquetoast ethical system, that should be it. And yet once you start thinking about what morality is – really thinking, the kind where you try to use mathematical models and formal logic – it opens up into these dark eldritch vistas of infinities and contradictions. The effective altruists started out wanting to do good. And they did, whole nine-digit-sums worth of good, spreadsheets full of lives saved and diseases cured and disasters averted. But if you really want to understand what you’re doing – get past the point where you can catch falling apples, to the point where you have a complete theory of gravitation – you end up with something as remote from normal human tenderheartedness as the conference lunches were from normal human food.

Fear and Loathing at EA Global

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Willems, Erik P., and Carel P. van Schaik. "The social organization of Homo ergaster: Inferences from anti-predator responses in extant primates."Journal of Human Evolution 109 (2017): 11-21.

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Guanlong wucaii

Early Theropod

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One set of studies has carefully documented the behavior of an alpha male chimpanzee in an open-plan zoo. The male initially collected and stored piles of stones early in the morning, to throw at zoo visitors later in the day as part of an aggressive threat display. When the zoo keepers responded by removing his stashes before the zoo opened each day to prevent this, he proved quite adept at concealing his stashes... Note that at all times when he collected and concelaed his stashes he was in a calm state, in the absence of the stimuli (human visitors) that would later provoke his rage.

Carruthers, Peter. The centered mind: what the science of working memory shows us about the nature of human thought. OUP Oxford, 2015. p 221

Discussing: 

Osvath, Mathias. "Spontaneous planning for future stone throwing by a male chimpanzee." Current biology 19.5 (2009): R190-R191.

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Human Population Size

Ambrose, Stanley H. "Late Pleistocene human population bottlenecks, volcanic winter, and differentiation of modern humans." Journal of Human Evolution 34.6 (1998): 623-651.