Of mouse utopias and men

DR ED­WARD DUT­TON asks whether a new in­ter­pre­taion of a clas­sic ex­per­i­ment warns of the death of hu­man­ity...

Fortean Times - - Contents - Dr Ed­ward dut­ton

Mice, like all an­i­mals in the wild, bat­tle the sav­agery of se­lec­tion. They are sub­ject to preda­tors, cold, star­va­tion and dis­ease. Male mice must fight it out to con­trol the largest harem of fe­males; moth­ers will re­ject runts among their off­spring. This means that only the mice that are phys­i­cally and men­tally best adapted to their en­vi­ron­ment pass on their genes. In ev­ery gen­er­a­tion, mice that have mu­tant genes – caus­ing poor im­mune sys­tems, phys­i­cal weak­ness or stu­pid­ity – are coldly cleansed from the pop­u­la­tion. Red in tail and squeak, this is nat­u­ral se­lec­tion – and un­til the In­dus­trial Rev­o­lu­tion we hu­mans were sub­ject to it as well.

Un­til about 1800, 40 per cent of us would die be­fore reach­ing adult­hood. And this wasn’t a ran­dom 40 per cent: in a so­ci­ety with no proper medicine, it was any­body who didn’t have a su­perb im­mune sys­tem. Com­pet­ing for sur­vival in this un­for­giv­ing world, in­tel­li­gence (which is about 80 per cent ge­netic) gave peo­ple a huge ad­van­tage, be­cause it al­lowed them to be­come wealthy and bet­ter able to pro­tect them­selves from dis­ease with health­ier food and liv­ing con­di­tions. So, ac­cord­ing to cut­ting-edge psy­chol­o­gists, in­tel­li­gence was se­lected for too, and there is clear ev­i­dence that those who lacked it had fewer sur­viv­ing chil­dren. 1 In 16th and 17th cen­tury Es­sex and Suf­folk, the richer 50 per cent of tes­ta­tors had 40 per cent more sur­viv­ing chil­dren than the poorer 50 per cent, some­thing that held roughly true through­out Europe. 2

What all this meant was that the pop­u­la­tion num­bers re­mained at the level the agrar­ian ecol­ogy could sup­port. This, in Eng­land, was less than six mil­lion. The In­dus­trial Rev­o­lu­tion changed all this, be­cause it pretty much put an end to nat­u­ral se­lec­tion, mean­ing that eco­nomic and sci­en­tific growth out­paced pop­u­la­tion growth. With in­oc­u­la­tions, rapidly ex­pand­ing med­i­cal tech­nol­ogy and sky­rock­et­ing liv­ing stan­dards, child mor­tal­ity fell from 40 per cent to less than two per cent: now, all the peo­ple with poor im­mune sys­tems and ge­netic health prob­lems – all the peo­ple (about 90 per cent of us!) with ‘high mu­ta­tional load’ – were able to pass on their genes, as were their chil­dren, grand­chil­dren and great-grand­chil­dren, lead­ing to an ever-grow­ing build-up of mu­ta­tion.

This is a unique sit­u­a­tion in hu­man his­tory. Pre­vi­ous civil­i­sa­tions – Greece, Rome, China – al­ways col­lapsed just at the be­gin­ning of an In­dus­trial Rev­o­lu­tion. But for rea­sons that are un­clear the Chris­tian West didn’t. It con­tin­ued se­lect­ing for in­tel­li­gence for longer – long enough for in­tel­li­gence to get high enough for the ma­jor break­throughs to oc­cur. So, what hap­pens to a species when you com­pletely re­move nat­u­ral se­lec­tion? Well, we know what hap­pens to mice: it’s fright­en­ing, all the more so be­cause it seems to be hap­pen­ing to us to­day.

In 1968, at the Univer­sity of Mary­land, ec­cen­tric Ten­nessee­born ethol­o­gist John Cal­houn (1917-1995) be­gan a ground­break­ing ex­per­i­ment: he cre­ated a ‘Mouse Utopia’. This was a ver­i­ta­ble heaven for mice in which there would be: (1) No em­i­gra­tion by lower sta­tus mice to sub­op­ti­mal habi­tats, as there would be abun­dant replica habi­tats and the utopia would be im­pos­si­ble to es­cape from. (2) No re­source short­age or in­clement weather. (3) No epi­demics. (4) No preda­tors. 3

In July 1968, four pairs of house mice were in­tro­duced into the 16 cell ‘mouse uni­verse’. Af­ter 104 days (Phase A), the first lit­ter was born, re­sult­ing in so­cial tur­moil as the mice learned to live to­gether. There­after, the pop­u­la­tion rose ex­po­nen­tially, dou­bling around ev­ery 55 days un­til it reached 620. This is, of course, ex­actly what hap­pened af­ter the In­dus­trial Rev­o­lu­tion: enor­mous pop­u­la­tion ex­pan­sion.

This marked the start of Phase B. At this point, pop­u­la­tion growth slowed un­til dou­bling oc­curred only ev­ery 145 days, just as we have seen in the West­ern pop­u­la­tion, where there is ‘be­low-re­place­ment fer­til­ity’. Pe­ri­od­i­cally, in Phase B, young born at this point would have their own young, con­tribut­ing to the growth of pop­u­la­tion in which mice, un­like in the wild, were able to be­come el­derly in sig­nif­i­cant num­bers, just like in the West.

By the end of Phase B, all the most de­sir­able space was filled with polyg­y­nous so­cial groups con­trolled by dom­i­nant males. The more dom­i­nant the male, the larger and more fer­tile his so­cial group tended to be. There were 14 so­cial groups com­posed of 150 adults. Each group was made-up of about 10 adults, in­clud­ing a dom­i­nant male, as­so­ci­ated males and fe­males, and their off­spring. There were 470 such off­spring and they had all re­ceived good ma­ter­nal care and early so­cial­i­sa­tion. So, there were three times as many younger than older an­i­mals, a far greater ra­tio than would ex­ist in the wild.

At day 315, Phase C be­gan and pop­u­la­tion growth slowed markedly. Nor­mally, more mice sur­vive to ma­tu­rity than can find so­cial niches and so these lower sta­tus mice will tend to em­i­grate in search of such a niche. As this was pre­vented, a large num­ber of males – un­able to suc­cess­fully com­pete for a so­cial niche – sim­ply with­drew phys­i­cally and psy­cho­log­i­cally from ter­ri­to­rial males and ganged up to­gether. They would oc­ca­sion­ally fight each other over triv­ial is­sues but they would do lit­tle else. Low sta­tus fe­males would with­draw to (less de­sir­able) high nest­ing boxes but were not ag­gres­sive to­wards each other. How­ever, ter­ri­to­rial males were con­stantly con­fronted with sub­or­di­nate males try­ing to take over their

Nor­mally, more mice sur­vive than can find so­cial niches

ter­ri­tory and, as there were so many of them, the abil­ity of ter­ri­to­rial males to con­trol their ter­ri­tory de­clined.

This left nurs­ing fe­males ex­posed to nest in­va­sion. The fe­males would then take on the role of the ab­sent male, be­com­ing ex­tremely ag­gres­sive and even gen­er­al­is­ing this ag­gres­sion to their own young: ba­bies would be ejected from the nest too young and aban­doned by their moth­ers dur­ing tran­sit to new nest sites. Con­cep­tion de­clined, while re­ab­sorp­tion of foe­tuses in­creased. This be­hav­iour hugely in­creased mor­tal­ity and ev­i­denced a so­ci­etal break­down.

Phase D – the death phase – be­gan. Pop­u­la­tion in­crease ceased on day 560. Af­ter day 600, no mice sur­vived past wean­ing. The last con­cep­tion was doc­u­mented on day 920. By 1 March 1972, the av­er­age age of the colony was 776 days, which was 200 days be­yond the av­er­age age of mouse menopause. On 22 June 1972, the pop­u­la­tion was just 122 – 22 male, 100 fe­male – and by May 1973 (1,720 days af­ter coloni­sa­tion) all the mice were dead.

Au­topsy re­vealed some bizarre things. Of the fe­males aged 334 days at au­topsy, only 18 per cent had ever con­ceived, whereas in the wild they would each have had five or more lit­ters by that age. The male equiv­a­lents of these bar­ren fe­males were known as ‘the beau­ti­ful ones’. They never sex­u­ally ap­proached fe­males and nor did they ever fight other males. They sim­ply ate, drank, and groomed each other, dis­play­ing autis­tic, ob­ses­sive ten­den­cies. Al­most all of the adult mice in Phase D were these two types, and so the colony died out.

The ex­per­i­ment is fas­ci­nat­ing in terms of un­der­stand­ing the post-in­dus­trial evo­lu­tion of hu­mans. Cal­houn put the col­lapse down to over­crowd­ing in­ter­fer­ing with the abil­ity of these highly so­cial an­i­mals to func­tion. But in 2017, Michael Wood­ley rad­i­cally rein­ter­preted what had hap­pened. 4 Wood­ley and his team showed that the colony was nowhere near over­crowded when the pop­u­la­tion growth de­cline be­gan. They ar­gued that we would ex­pect all health prob­lems, both phys­i­cal and men­tal, to be in­ter-re­lated be­cause they broadly re­flect the same thing: high mu­ta­tional load. This is why left-hand­ed­ness (a re­flec­tion of mu­ta­tion) is cor­re­lated with poor phys­i­cal and men­tal health and why autism (a strong marker of mu­ta­tion) is cor­re­lated with poor health.

Se­condly, Wood­ley’s team ar­gue that due to the com­plex­ity of the brain, be­hav­iour would be ex­tremely sen­si­tive to mu­ta­tion ac­cu­mu­la­tion. By ex­ten­sion, in so­cial an­i­mals, where be­hav­iour is any­way com­plex, even small ac­cru­als in mu­ta­tion can lead to patho­log­i­cal forms of be­hav­iour and the rapid break­down of so­ci­ety. This is, in part, be­cause be­hav­iour is sig­nif­i­cantly learned in so­cial an­i­mals. This means that if mu­ta­tion in­ter­feres with the teach­ing of some use­ful be­hav­iour, even those who don’t have what Wood­ley calls ‘spite­ful mu­ta­tions’ will be im­pacted. Imag­ine if, due to some mu­ta­tion, you get more and more peo­ple who be­lieve you shouldn’t kill for meat. As they get larger in num­ber, so­cial pres­sure to con­form will be placed even on those who lack the mu­ta­tion and they will no longer be taught the de­spised skill.

Ba­si­cally, Wood­ley avers, the mice were evolved to have in­stincts that al­low mice to sur­vive. Ev­ery gen­er­a­tion, mu­tant mice would have been born who did not have these in­stincts: mice with no de­sire to breed, males with no wish to fight, fe­males with no ma­ter­nal in­stinct, fe­males with a male-like de­sire to fight. How­ever, these mu­tant mice would have had other mu­ta­tions – poor im­mune sys­tems or phys­i­cal fit­ness – mean­ing they wouldn’t have sur­vived to have chil­dren. In the Mouse Utopia, of course, they all sur­vived, many of them had chil­dren, and, even­tu­ally, they were the over­whelm­ing ma­jor­ity of the pop­u­la­tion. The rem­nant ‘nor­mal mice’ found that even they were im­pacted by this change and it got to a point where breed­ing stopped.

Wood­ley’s team ar­gue that this ‘Mu­ta­tional Melt­down’ is hap­pen­ing in the West. There’s no ques­tion that mu­ta­tional load is very high: hence in­creas­ing lev­els of autism, men­tal ill­ness, al­ler­gies, en­tirely ge­netic dis­or­ders and even left­hand­ed­ness. They also doc­u­ment a rise in ‘spite­ful mu­ta­tions’, which cause peo­ple to act against their own ge­netic in­ter­ests. Ex­am­ples in­clude mu­ta­tions that make peo­ple want to not have chil­dren or heav­ily de­lay do­ing so. And if these peo­ple in­flu­ence so­ci­ety, they can per­suade even non-car­ri­ers of these genes to act in a self-de­struc­tive way.

Mu­tants can also un­der­mine struc­tures, such as re­li­gion, which help to pro­mote group in­ter­ests. Many evo­lu­tion­ary psy­chol­o­gists agree that re­li­gios­ity (which is about 40 per cent ge­netic) is ba­si­cally a God­man­dated means of pro­mot­ing evo­lu­tion­ary im­per­a­tives such as big fam­i­lies, group loy­alty, and eth­no­cen­trism; eth­nic groups, even Euro­pean na­tions, have been shown to be ex­tended kin­ship net­works with clear ge­netic bor­ders. 5 As a con­se­quence, ar­gues Wood­ley, mod­ern lib­eral ide­ol­ogy – far from be­ing an in­di­rect means of ge­netic preser­va­tion – would in fact re­flect a sick so­ci­ety’s grow­ing de­sire to de­stroy it­self.

Does this mean that we are go­ing to die out? Hu­mans are not mice. There’s no sci­en­tist con­trol­ling us. We are the sci­en­tists who have built our own utopia. And Wood­ley has shown that due to the weak se­lec­tion in this utopia, we have not just stopped se­lect­ing for in­tel­li­gence, we are be­com­ing less in­tel­li­gent. 6 IQ is neg­a­tively as­so­ci­ated with fer­til­ity, seem­ingly be­cause the more in­tel­li­gent are more ef­fi­cient users of con­tra­cep­tion, and more in­tel­li­gent women heav­ily de­lay or com­pletely re­ject moth­er­hood.

Ac­cord­ingly, IQ is go­ing down and some re­searchers are ar­gu­ing that, even­tu­ally, civil­i­sa­tion will col­lapse back to a new Dark Age in which nat­u­ral se­lec­tion will re­assert it­self, re­li­gion will make a come­back, and hu­man­ity will sur­vive. 7 What­ever hap­pened to the utopian mice, hu­man­ity’s obit­u­ary shouldn’t be writ­ten just yet.

LeFt and oP­Po­sIte: John Cal­houn in his mouse utopia.

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