Raping otaries and psycho chimps

From metapsychoanalysis, was derived the notion of metapsychic evolutionary principle, and which serves as an heuristic to put in perspective animal behaviors, how likely they are for a given species of a given intelligence and lifespan (in short, its stature on the evolutive ladder) and what eventual discrepancies from expectations could teach us.

We view possessing polymorphic sexual instincts (like ours) unrelated to breeding, as an evidence of metapsychic evolution, as the potent sexual drive is transcended and put to a better use. While we perceive intelligent yet immoderately unreasonable or vicious species as evolutionary dead-ends in the grand scheme of things. Natural selection might produce all sorts of combinations in terms of species-wide personality traits, instincts and cognitive abilities. Not all of these might make sense on a higher level than the immediate survival of the species.
Staying within a restrictive reductionist perspective, other elements factor in the continual survival of a species along millions of years up to geological times.

A species might be well endowed for its immediate environment, but not adapted enough to support any ensuing ecological change of any kind, local as well as global. On the opposite, species endowed with a general capacity for physiological or behavioral adaptations (in one individual or a few generations) like those trees featuring diverse ecotypes for the same genetics depending on the altitude, from small corpses to very tall trees. The issue is, one can assume such adaptations to pack a lot of information, taking a long gradual time to produce… meaning this kind of adaptation at initial low levels of development might be quite poorly responsive to too strong selective pressures, if we only considered neodarwinist mechanisms.

Yet, there might exist another kind of incompatibility in the long run. When contemplating species like orca, which allegedly savagely hunt and kill dolphin (though never humans, strangely enough). We tend to expect intelligence to acknowledge intelligence, not consider it as food. An reason would be a lack of instinct to prey on us, not having evolved in our vicinity. However lower predators (cats, weasels) usually have no issue munching entirely new preys to extinction whenever transported to new islands.

No species whose intelligence borders on our own to some capacity, mainly cetaceans, elephants and great apes, ever considered us as a food, despite often a consistent overwhelming physical disadvantage on our side. Simply put: monkey sees us, monkey bigger, monkey should tear our arms out and eat them.
Yet it doesn’t happen.

We would expect constant cruelty or unscrupulousness to be strongly associated with a strictly breeding-minded sexual behavior. Indeed a hardcoded predatory mindset goes hand in hand with a highly territorial, highly competitive nature, while mating behaviors are seasonale (matching oestrus cycles closely), see fights over partners and little long-lasting relationships - beyond sometimes - those limited to a couple raising their offspring.

Despite boasting a bigger brain than dolphins, orcas match those boxes well, whereas dolphins (while still predating on fish) show both a lot more empathy and social complexity, and a sexuality much the same as bonobos’, save for the anatomical differences. Orkas’s playful nature regards to food (much like a cat) hasn’t really been observed for dolphins either.

This essential bipartition based on the attitude toward love, pervades all of our understanding of evolution and psychology, human and non-human alike, and this shouldn’t come as a surprise, if - as we believe - the spiritual layer of reality and its comprehension indeed is the most important thing in life, the very purpose of life (intelligent life in particular) in the long run, of existence itself.

It is bound to be reflected by evolution: species don’t just become spiritual because. It comes with a few requirements, which might or might not come up as probable or easy to check, as natural evolution readily rewards opportunistic, amoral tendencies.

One should expect older intelligent species (which could isolate themselves from predation-based natural-selection for some time) to align with some moral standards, with time, and most sapient species at any given time to show some control over their opportunistic tendencies, merely by virtue of evolutionary pressures.

In the end, extrasensory abilities are the single most generalist and powerful adaption any genre could muster, ultimately allowing survival despite any odds through prescient perception of dangers, up to (as some humans show, and in the past all Neanderthals) an absolute domination of the planet, the environment, and the laws of physics themselves. The problem is, it takes very specific conditions to advance to the point of sustaining its continuous improvement.

Unless your whole group is nice too, ruthlessness tends to be more adaptative as it grants dominance, without which one ends up childess, dooming that genetic progress a mutant may represent.

Which is why I get particularly angsty and tensed, when I read about wild animals showing very perplexing - downright insane - behaviors, spitting not only at the face of evolution as we understand it, but of our personal experience of raw animals too.

Justifying alcoholism

Constantly news media relate stories of drunken animals, with the obvious intent to clear our conscience, ascribing our addiction to alcohol not to people being utter degenerates (who would survive a week in the wild) but accusing nature itself of having made us potential drunkards. There could not be a better copout strategy than finding drunk animals.
Even if half those cases are fake and the remaining highly misguiding, and we will show it. It wouldn’t even warrant my time writing this, if a number of scientists too had not been called to accredit those myths.

The problem is similar to that of drugs or other natural psychotropic/psychogenic substances. It can be summed up in 3 points:

  1. Does it exist in wild nature in a concentration great enough to produce any physiological effect ?
  2. If so are animals instinctively guarded against too high a concentration ?
  3. Can they acquire a preference for it, if so in what conditions ?

We will start with alcohol, the most easily - relatively speaking - psychoactive chemical compound, as a natural product of sugar fermentation in fruits, nectar or sap.
Indeed the first question one must wonder even assuming all mammals had an automatic appeal for alcohol, is: could we even enough to get drunk ?
Obviously that will depend on several factor, not just dietary availability (with primates, the amount of fruits rotting on the ground), but the composition of said fermented/alcoholic food in the animal’s diet, and its metabolic rate. By virtue of natural selection, animals routinely eating a big proportion of sugar (especially if susceptible to ferment) will have have a bigger liver relative to their size, and higher levels of Alcohol Dehydrogenases (ADH), the enzymes responsible for breaking down ethanol.

And the physiological tolerance to alcohol concentration in our blood also differ, so that only experimental results can decide what does or not cause ebriety.

We discovered that seven mammalian species in a West Malaysian rainforest consume alcoholic nectar daily from flower buds of the bertam palm (Eugeissona tristis), which they pollinate. The 3.8% maximum alcohol concentration (mean: 0.6%; median: 0.5%) that we recorded is among the highest ever reported in a natural food.
Nectar high in alcohol is facilitated by specialized flower buds that harbor a fermenting yeast community, including several species new to science. Pentailed treeshrews (Ptilocercus lowii) frequently consume alcohol doses from the inflorescences that would intoxicate humans. Yet, the flower-visiting mammals showed no signs of intoxication. Analysis of an alcohol metabolite (ethyl glucuronide) in their hair yielded concentrations higher than those in humans with similarly high alcohol intake.
in 2008, Chronic intake of fermented floral nectar by wild treeshrews

Assuming an uncontrolled natural disposition for it, for megafauna (animals our size or bigger) to get drunk one would require enormous amount of fermented fruits at the same place and time incompatible with any notion of instinctive regulation, so that an automatic vomitive reflex would kick in before the alcohol level could rise in any capacity. It is a fact that natural food almost never reach beer-levels of ethanol, let alone degrees higher than 3%.
So in any case to argue an hypothetical taste for a 1 to 1.5% degree in food still wouldn’t account for humans’ addiction or taste to the likes of cidar (3%) beer (4.2%) whine (5%) sake (15%) or whisky (40%). The tolerance to a certain substance selected by evolution has to reflect the conditions found in our environment, which never included anything higher than 2% at the very worst in any appreciable quantity. Therefore no evolutionary argument can explain a taste for alcohol beverage.

Only the paradoxal physiological state induced by cooking, plus the early anihilation of our dietary instinct could, plus a strong cultural psycho-cultural conditioning to do away with the inborn aversion every child experiences. That is why captive primates have been seen liking some level of alcohol:

This analysis aims at determining to what extent spontaneous alcohol drinking in adult male rhesus monkeys (Macaca mulatta) analysis aims at determining to what extent spontaneous alcohol drinking in adult male rhesus monkeys (Macaca mulatta) represents ethanol-directed behaviour.
It is shown that in a condition of free access to an ethanol/water solution (2 percent v/v) and drinking water, alcohol drinking was initiated in all subjects (n = 4) within a few days, without any specific induction procedure.
When ethanol concentrations in the solutions increased, consumption of ethanol solutions decreased, of drinking water increased, and of total water decreased. Net ethanol intake from a certain solution was influenced by its concentration and the concentration of the concurrently available solution. After an initial increase, total net ethanol intake remained relatively constant. Consumed amounts of ethanol (on the average 2-6 ml.kg- ~ per day) could lead to notable blood ethanol levels.
The observed alcohol drinking is interpreted as resulting from a central reinforcement of ethanol intake and avoidance of negative, potentially harmful effects of ethanol.

Ages between 7 and 9 years, and each housed in a separate cage in the same room
Diet consisted of regular monkey pellets (over 200 g) provided at 0910 hours in the morning, supplemented with fruit at 1340 hours and a slice of bread at 1540 hours. The room was temperature.

in 1989, Analysis of spontaneous alcohol drinking in rhesus monkeys

Considering that:

  • The constant digestive unease cooked food brings
  • The allegued digestive effect of alcohol at low-level1 (accelerating digestion and gut mobility, in simple words pooping)
  • The capacity of animals with big brains (non-human primates) to offset more immediate reactions in order to repeat a positive outcome they experienced
  • the suppression of alliesthesy, the important digestive discomfort and heavy ssleep cooked food brings about
    I think those poor sods fed on biscuits instead of seeking tipsiness simply sought the momentaneous relief from permanent intestinal discomfort and the speeding up the expulsion of denatured molecules that a definite amount of alcohol provided.

Secondly, the precise regulation in ethanol consommation observed might allude to a certain dose of fermentation (indicated by ethanol) being not just benign but desirable, due to us having adapted to it. Some even spontaneously forms in our guts. The monkeys may have just sought to compensate for the lack of it in their lab diet.

Typically, children learn to break open aversion barriers to coffee and alcohol by masking their taste with sugar, prefering sweat beers or cidar to wine. Sugar + ethanol might as well explain why people start drinking, the combination unconsciously reminding their body of fermented fruits.

Integral rawfoodists keep that alliesthetic disgust for fruits even slightly too fermented, meaning that beer-level fermentation just isn’t attractive in the slightest for wild primates, quite the opposite.

Despite of good predictions and evidences so far, the drunken monkey hypothesis is laughable, because such low concentrations do not compare at all with that of our drinks.
The second arguments doesn’t hold water either nor would it be justified by evolution, as by definition an hypothetical feeding stimulant effect could not be inherent to a simple chemical such as alcohol but would have developed as an adaptive response. However simply eating more has no value whatsoever, we eat when we must, how much we must, and we’re very picky at it. All creatures down to the simplest bacteria are wired with this drive, the strongest in existence. It needs no outside incentive to kick in or remind the animal that it should it.

Both bees and vertebrates show (except the rare few species surviving on a single source of course), show very specific preferences. Even total predators will choose with great care the parts to ingest (innards over anything else). Bees will favor some species of flowers over others.
Calories (for the overwhelming majority of vertebrates) are not the most important for one’s equilibrium, they represent only one need: energy. We tolerate occasional or even chronic low amounts very well, regulating our activity and metabolic rate as a consequence. Calories, for primates at least, definitely are not the limiting factors in their diet, unlike vitamins and the thousands of micronutrients.

Ergo by virtue of evolution no animals (except perhaps extreme specialists) that lived with a given food range (or anything remotely close on the molecular level) for a few tens of thousand years could develop in contact with a given food range can develop to associate automatically (bypassing alliesthetic regulations) a specific food component to a reward circuit.


But exposition of the cocktail of thousands of new chemical compounds each cooking recipes magnifies reward circuits a hundred times, creating evolutionary counter-intuitive though a powerful dependency neurologically identical to that of drugs:

A well-known characteristic of addictive drugs is their ability to cause repeated, intermittent increases in extracellular dopamine (DA) in the nucleus accumbens (NAc). We find that rats with intermittent access to sugar will drink in a binge-like manner that releases DA in the NAc each time, like the classic effect of most substances of abuse. This consequently leads to changes in the expression or availability of DA receptors.
Intermittent sugar access also acts by way of opioids in the brain. There are changes in opioid systems such as decreased enkephalin mRNA expression in the accumbens (Spangler et al., 2004). Signs of withdrawal seem to be largely due to the opioid modifications since withdrawal can be obtained with the opioid antagonist naloxone. Food deprivation is also sufficient to precipitate opiate-like withdrawal signs.
in Is sugar really as addictive as cocaine? Scientists row over effect on body and brain

Unsurprisingly these studies (yes, plural) raised a whole lot of controversies, since it amounts to calling nearly everyone liking sweets a druggie.
These conclusions provoked many outraged reactions:

Tom Sanders, emeritus professor of nutrition and dietetics at King’s College London said that it was “absurd to suggest that sugar is addictive like hard drugs.”
While it is true that a liking for sweet things can be habit-forming it is not addictive like opiates or cocaine, said Sanders. Individuals do not get withdrawal symptoms when they cut sugar intake.

Except that people very high on industrial sugar totally do. This kind of criticism smells a lot like a defense mechanism to me ! How on Earth does the relative peace of getting one’s dose at regular interval proving that it’s not a drug ? People are addicts to tobacco and it doesn’t seem to alter their personality as long as they can smoke whenever they want. Remove it and things change.

Robert Lustig, professor of paediatrics at the University of California San Francisco said he shared the concerns of DiNicolantonio and colleagues. I do believe that sugar is addictive, based on its metabolic and hedonic properties he said. Lustig has previously argued that sugar is the alcohol of the child. However, while he said he believed sugar was a drug of abuse, he considered it a weak one, on a par with nicotine, rather than drugs like heroin.

I agree, cooking as a whole appears much harder to withdraw from than mere just white sugar (or saccharine). It may be essentially socio-psychological - arguably ? - but to master the will to forgo all recipes and follow one’s instinct is more difficult than to stop drinking or smoking, one paar with cocain addiction. As for the preference for natural sources of alcohol in the wild, no study was every conducted.

Studies of inborn preference of alcohol in the wild for higher vertebrates are absent. We do have a study about chimpanzees in the wild but with proper alcohol, and not in a form we could possibly ever evolve to regulate. Fermented fruits lie on the ground every now and then. But this ?

Chimpanzees at Bossou ingest this alcoholic beverage, often in large quantities, despite an average presence of ethanol of 3.1% alcohol by volume (ABV) and up to 6.9% ABV. Local people tap raffia palms and the sap collects in plastic containers, and chimpanzees use elementary technology — a leafy tool — to obtain this fermenting sap. These data show that ethanol does not act as a deterrent to feeding in this community of wild apes, supporting the idea that the last common ancestor of living African apes and modern humans was not averse to ingesting foods containing ethanol.
in Tools to tipple: ethanol ingestion by wild chimpanzees using leaf-sponges, Kimberley J. Hockings et al.

Fermented sap on the other hand lies outside the range of what could occur in nature, and requires a human artifice to brew. Chimpanzees drink sap from the tree, never brewing for a minute, let alone a week. A minute of reasoning should suffice to realize that evolution was in no way required to guard us against fermented sap, no more than against any other form of brewage impossible to find in nature.

As all forms of processing brewing is likely to bypass natural regulations. So to assume from the behavior of so-called wild chimps eating who-knows-what that the common ancestors of all primates developed an inborn tendency for alcoholism goes beyond stupidity, into the realm of willful deceit of public opinion.


so-called drunk birds, in fact run over by a car

Some birds have a very specialized diet, consisting mostly if not totally on fruits. So like the treeshrews, they evolved to ingest digest and excrete in a matter of an hour up to the equivalent of a man of 70 kg eating 14 kg at once, not even throughout the day. Their metabolism, as per the requirements of constant flight as well as thermogenesis (in both case the smaller the less efficient energy-wise) is - as general rule - much faster than mammals’, and the smaller the faster.
Hence for a given feeding/digestion time they will be in contact with a lot more alcohol per gram of body mass than would frugivores among mammals. Then those levels quickly dwindle as the ethanol (then more importantly, its toxic subproduct acetaldehyde) breaks down assaulted by enzymes.

But do birds always cope with their diet ? Natural selection would say Yes of course duh but people keep reporting slews of wild birds dropping from the sky, running into windows and cars, singing on the street in groups oblivious to human, unable to fly off. Seemingly completely hammered. And people love to report it, incriminating fermenting berries.

See the New York Times, in 2018 , giving io this self-conforting popular telltale of drunken birds.
Scientifics have been debating for decades by now, owning to the difficulty of analyzing the lots of dead or allegued drunken birds by foresensic pathologists, in order to ascertain common causes of possibly unrelated accidents. One difficulty lies in the variety of species involved2.

In some cases, the science is settled:

Every fall, flocks of robins migrate to warmer climates to escape dropping temperatures. They use up a lot of energy and Bay Area gardens have become popular pit stops along the way. The starving birds usually stay a week or so to dine on tasty berries and worms before continuing their journey south.

In reality, the birds are just suffering the aftereffects of a serious case of overeating. When the robins land in your yard, they are starving. They dive headlong into the berry bushes in a feeding frenzy, made all the more frantic by each other’s competitive actions as they fight to see who can eat the most berries in a single gulp.

Bird life is further complicated when suddenly elevated blood sugars, from gorging on sweet berries, contribute to the avian hyperactivity. This overeating also results in top-heavy, overweight birds staggering around the sky as they try to deal with the effects of gravity on dramatically modified flight characteristics. Filled to the brim with 10 to 15 juicy berries apiece, about 20 percent of each bird’s natural weight, they are no longer graceful fliers.
Those fresh, unfermented, nonalcoholic berries are a source of nutritious food for many wild creatures. The pyracantha berry is the potato of the bird world.
The ripening process continues from October through January, depending on subspecies of berry, air temperature, moisture, etc.
It is quite obvious there is a marked difference in flavor between ripe and unripe berries. I’ve seen whole flocks of robins skip over entire bushes because the berries obviously didn’t taste just right to them.

Gary Rogue in Drunk robins: It’s a myth that those birds are drunk on berries

That behavior alone, ethanol-induced stupor or not, doesn’t seem normal at all. Both populations and needs should be tailored to the quantities and diversity of food, so that animals shouldn’t feel any such rush, not to the point of killing themselves, when less ripe fruits exist. If for some reason in tens or hundreds of thousands of years that very parameter (availability of ripe berries) did not change, then birds would adapt to eat on less riped ones. And coevolution - birds spreading seeds by shitting them - would favor species ripening earlier or longer.
The fact it didn’t happen, means that there used to be enough food so that such selection pressure couldn’t increase.
It doesn’t take a galaxy-brain to realize that in the past, a mere 50 years ago, urbanization in the US wasn’t nearly as extensive and intensive as today. There were a lot more trees, more diverse too, the farther back in time we go… up to the Holocene’s onset, the Younger Drias Boundary .

So, environmental depredation, as usual.

It is possible too that in some cases some birds fall back on back on less appealing, too fermented berries pushing the with health consequences. Maybe.
How much of them is highly debatable and was debated to death.

This report describes the gross and microscopic and toxicological findings from 21 to 90 Cedar Waxwings (Bombycilla cedrorum) that were submitted for necropsy after death caused by flying into stationary hard objects.
A significant finding in our study is the detection of 1,000 ppm ethanol in the liver of one of nine birds, 260 ppm in two of six pools of intestinal contents, and 700 ppm from the out-of-state submission of one of two gastrointestinal pools analyzed. Ethanol was not detected in eight livers, in six pools of crop, and six pools of gizzard contents. In our study, the primary cause of death in the 21 birds necropsied was hepatic rupture and severe internal hemorrhage from blunt trauma.
In a feeding trial of Bohemian Waxwings, blood ethanol levels were found to be as high as 20 and 50 ppm, and it was suggested that these levels are so low that they cannot be assumed to have any influence upon the bird’s flying ability and behavior. However, Cedar Waxwings used in the study were twice as large as in our report.
Alcohol dehydrogenase (ADH) activity is high in fruit eaters and low in seed-eating birds. Prinzinger and Hakim (1996) reported that the combination of the high ADH activity and the low concentration of alcohol normally found in fermented fruits and berries means that birds have no problem in coping with alcohol. Others have estimated that, if the Waxwing ate 30 g of rowan berries in 1 h, the alcohol content in the water phase of the bird would be 0.5 %, in spite of its alcohol elimination. This high ethanol concentration might be expected to affect the bird’s ability to fly.
in Strong circumstantial evidence for ethanol toxicosis in Cedar Waxwings (Bombycilla cedrorum)

To conclude with this:
Lots of hypotheticals, we do not know what levels would produce what effect exactly - we cannot translate directly in blood levels either, hence not compare directly with humans. In this sample we can conclude that intoxication may likely have contributed, though overeating and sugar levels might have factored more (or even solely) in these deaths.

And no one ever showed that (wild) birds prefer fermented berries so in no way did these happenings ever help condone our alcoholism:

Either birds aren’t drunk, or chose the wrong fruits by mistake (highly improbable) or were forced to rely on them out of necessity.


In 2004 has been published Lethal aggression in Pan is better explained by adaptive strategies than human impacts by Wrangham & Wilson, according to which the regularity and pattern of killings in chimpanzees reveal a vicious, demonic (the term is theirs) and violent male nature, bent on treating females like resource, and resort to bloodbath whenever it seems advantageous for their selfish interest. Are chimpanzee males driven by the love of their group and the wish to get along like we would expect (a bit naively perhaps ?) any evolved critter (such as intelligent aliens) to behave ?

We documented killings by chimpanzees in 15 of 18 communities (58 observed, 41 inferred, and 53 suspected cases;
Most victims were members of different communities from the attackers (62 of 99 cases; 63%) and thus not likely to be close kin. This difference is particularly striking given that chimpanzees could potentially attack members of their own community on a daily basis, but rarely encounter members of other communities.
Intercommunity killings mainly involved parties with many males attacking isolated or greatly outnumbered males or, more often, mothers with infants. For 30 cases in which the number of adult and adolescent males and females on each side were known, attackers outnumbered defenders by a median factor of 8.
Most intercommunity killings thus occurred when attackers overwhelmingly outnumbered victims. Several robust patterns emerge from these data. Killing was most common in eastern chimpanzees and least common among bonobos.
Among chimpanzees, killings increased with more males and higher population density, whereas none of the three human impact variables had an obvious effect. Male chimpanzees killed more often than females, and killed mainly male victims; attackers most frequently killed unweaned infants; victims were mainly members of other communities (and thus unlikely to be close kin); and intercommunity killings typically occurred when attackers had an overwhelming numerical advantage.
The most important predictors of violence were thus variables related to adaptive strategies: species; age–sex class of attackers and victims; community membership; numerical asymmetries; and demography. We conclude that patterns of lethal aggression in Pan show little correlation with human impacts, but are instead better explained by the adaptive hypothesis that killing is a means to eliminate rivals when the costs of killing are low.
Lethal aggression occurs within a diverse set of circumstances, but is expected to be most commonly committed by males; directed towards males; directed towards non-kin, particularly members of other groups; and committed when overwhelming numerical superiority reduces the costs of killing.
Wrangham & Wilson in Lethal aggression in Pan is better explained by adaptive strategies than human impacts

In 2010 as a responses to criticisms regards to these ideas (already quite clear) in Chimpanzee violence is a serious topic: A response to Sussman and Marshack’s critique of Demonic Males: Apes and the Origins of Human Violence, they stated:

Coalitionary killings among chimpanzees are certainly rare. Nevertheless current estimates suggest that they occur at a frequency not very different from war deaths among human pre-state societies (which themselves occur at a substantially higher rate than war deaths in twentieth-century industrial nations, Keeley 1996).
In a survey of nine study communities in the five longest-studied populations of chimpanzees with more than one community, Wrangham et al (2006) reported that the median risk of violent death for chimpanzees from inter-community killing (69-287 per 100,000 per year) fell in the same order of magnitude as the median reported values for rates of death from warfare among subsistence-society hunters and farmers (164 and 595 per 100,000 per year, respectively).

Lowe et al. arrived at similar conclusions regarding infanticides, as the product of naturally evil males:

Infanticide is well documented in chimpanzees and various hypotheses have been proposed to explain this behavior.

Here we present an analysis of the largest dataset of infanticides from a single community of chimpanzees, a full record of all intra-community infanticides and failed attempts at infanticide over a 24-year period for the Sonso community of chimpanzees in the Budongo Forest, Uganda. Our data best support the sexual selection hypothesis for infanticide.

As lactation prevents females from ovulating (McNeilly et al. 1994), dependent infants are an obstacle for males seeking reproductive opportunities. A younger infant is a larger obstacle, as it represents a longer period until the mother will be sexually receptive again. This hypothesis predicts that the majority of infants killed by infanticide should be very young (infants < 1 year).
In addition to infants being very young [sexual selection hypothesis prediction one (S1)], killers should not kill their own infants (prediction S2), and should often father replacement infants (prediction S3). Attackers should be males (prediction S4), and victims should be neither predominantly male nor female since both represent an equal obstacle to mating with the mother (prediction S5). Mothers should not usually sustain severe injuries (prediction S6): they are not the primary targets, and severely injuring a female may compromise future mating opportunities..

in Intra‑community infanticide in wild, eastern chimpanzees: a 24‑year review, 2019

Their conclusions based on less than 22 to 30 more cases than the mixed results 2014 study on killings were:

Of the 35 intra-community infanticides reported by Wilson et al. (2014), excluding those from our study site (the Budongo Forest Reserve, Uganda), in eight instances the attackers were male, in six instances they were female, while both sexes were attackers in two instances; the sex of the attackers was unknown in the remaining 19 cases. Male infants were killed more frequently than female infants (19 versus seven incidences, respectively).

There is a simple explanation, which though I can not prove by lack of data, is nevertheless an absolute certitude: we have been feeding shit to animals from 1975 onward, in most observation sites, or at least those featuring murders.
This much has been confessed by none other than Jane Goodall, which had already before then, beeng going on with her observations for 14 years, and consistently described them the same as we do with bonobos: uniformly gentle, pacifistic, collectivist (caring for the group more beyond one’s self-interest), joyously sharing females and vice versa.

Then, she started limited human-controlled feeding", which significantly changed their behavior from pacifism to aggressivity, competitiveness, opportunistic violence.

Typically, from then on males started being described as fighting over females like bulls, with females barely keeping the group together and outright wars erupting, be it inter- or intra-community.

Other indices of chimps not being in their natural state include frenetic, mindless breeding behaviors absolutely typical of cooking feedback:

of Female Chimpanzees Observed in the Kalinzu Forest, Uganda, Intra‑community infanticide in wild, eastern chimpanzees: a 24‑year review, 2019"}
We observed extremely high frequency of promiscuous mating of female chimpanzees in the Kalinzu Forest, Uganda. During the observation in 2001, three females copulated for 3.1 times per hour in average. In an extreme case, a female copulated for 39 times within 343 min, and she sometimes copulated with two males within one minutes. They copulated with most of adult male chimpanzees found in the party and there was no aggression between male chimpanzees.

The contrast is too striking, this breeding and aggression overdrive are characteristic of cooking feedback. The fact some communities show no violence whatsoever while some others are legit batshit insane has no other explanation.
Some promoted the idea of local ape cultures, that young chimpanzees when raised in, could adopt and thus display a slew of varied behaviors all within the range of what is genetically possible for them.

But I disagree with this idea too: the separation of nature and culture in humans is a dire mistake, stemming from cooked food. Cultures as we know them should not exist.
To be precise material cultures (habits pertaining to tool-use) of course need to be learnt over time, and some ape populations show different habits. But slightly different food sources shouldn’t impact psychology and instincts in the slightest: these are a direct product from genes. Humans vary so much in personality doesn’t come from our superior intelligence or whatnot but is pathological, caused by diversified cooked diets, their chaotic effects on the nervous system and equally chaotic interactions with innate personality traits. Lastly, gradually socially-expected norms decant in the form of cultures with its bells and whistles.

What we have been observing for decades is the alteration of behaviors with any form of processed food (the more processed the worse) compared to raw paleolithic food, so, imitating wild animals. For us humans, it meant imitating chimpanzees.
From our perspectives, it is very likely that the entire world’s been afflicted with low levels of pollution, plastic bits or otherwise, altering maybe considerably, natural behaviors. Me and a bunch of other individuals have been observing this within the context of alternative diets, both on our persons (actually, thousands of people, though most were more concerned with diet than with psychogenic effects) and animals alike.
Molecular stress (any unnatural amount of molecules not found in the species’ natural environment or diet) appeared to almost universally make animals less alert yet more excited, with increased levels of breeding behaviors and exacerbed secondary sexual character traits like territorial dominance male aggressivity and female passivity, as shown at least for mice in Abnormal behaviours induced by chemical pollution: a review of the evidence and new challenges by Sarah M. zala & Dustin J. Penn.
Simulacra (as defined by Konrad Lorentz, displays whose real purpose is different from the real one) go completely out of control. In the case of chimpanzees simple brawls aimed at deciding new hierarchies, can change into seemingly organized murders of the kind only humans are capable of.

Until the complete natural environment (in terms of food range at least) of a population has been reconstituted to a significant degree within a perimeter, speculating about ape nature like the likes of Wrangham do is ridiculous.
Actually I am positive these people find a perverse pleasure in tarnishing the public image of animals, almost on a sexual level. I read countless articles which would put to shame tabloids like the Sun.

I believe the mainstream public is simply too eager to accept any pseudoscientific theory relieving them of the guilt borne of comparing harmonious functional primate societies with our highly dysfunctional, messed-up societies. It is easier to blame genetics and nature, than to put the effort into correcting one’s lifestyle and culture.. In 50 years there might be almost nothing left of big wild animal species, a decaying world.

  1. Effects of red wine on accelerated gastric emptying following Nissen fundoplication
    The appetizing effect of an apéritif in overweight and normal-weight humans
    Why Alcohol Makes You Poop (And How to Avoid a Bathroom-Filled Morning After)  ↩︎

  2. The Waxwings metabolized alcohol (with the 1 g/kg dose) 3.3 times as fast as the Starlings and 7.2 times as fast as the Greenfinches, while the Starlings metabolized it 2.2 times as fast as the Greenfinches. The rate of alcohol metabolism was approximately 40 mg/kg/h faster after the larger dose than after the smaller dose in all three species . The difference was significant in the Starlings (P<0 .001) and the Greenfinches (P<0.01) but not with the Waxwings because of their larger variation.

    ADH activities and isoenzymes:
    The ADH activity of Waxwing liver, measured as mpmol/min/mg protein was on the average 15 times as high as that of Starlings and 6.2 times as high as that of Greenfinches (Table 3) . In Waxwings the liver constitutes 4.9 % of the total body weight ; in both Starlings and Greenfinches only 2.8 %. The whole liver ADH activity of Waxwings is 23 times as high as that of Starlings and Greenfinches.

    Eriksson, K. & Nummi, H. in 1982, Alcohol accumulation from ingested berries and alcohol metabolism in passerine birds