| 1301/
Relative to its body weight the chimpanzee has the biggest
testicles of any primate. They weigh 120 grams - about the
weight of the meat in a quarter-pound burger, and constitute
0.3 per cent of its body weight.
1302/ Some 120 males
are conceived for every 100 human females; but just before
birth the ratio has been reduced to 110:100 by the male's
extra vulnerability to miscarriages, many caused by chromosomal
abnormalities. In terms of live births males outnumber females
by only 106 to 100, and the extra vulnerability of males continues
throughout life so that by the age of seventy the ratio at
conception is reversed and there are 120 women for every 100
men.
1303/ The average human
chromosome carries between 10,000 and 1,000,000 genes. Recombining
can occur between any two genes, so that two parental chromosomes
can recombine into over 100,000 different offspring. There
are 23 pairs of chromosomes, so one cell could give rise to
more than 10 to the power of 115 different gametes (100,000
combinations of 23 chromosomes).
1304/ Astronomers estimate
that in the entire visible universe, all the stars of all
the galaxies, there are altogether roughly 10 to the power
of 80 fundamental particles - protons, neurons and electrons.
So it would take 10 to the power of 35 universes like our
own to provide one such particle to represent every possible
unique human being.
1305/ The number of chromosomes
varies from species to species, although all members of a
species have the same number. A human being has 46 chromosomes,
a fruit fly 8 and some ferns more than 600.
1306/ Whilst we share
almost 99 percent of our DNA with the chimpanzee and the gorilla;
they have twenty four pairs of chromosomes and humans have
twenty three. It has been established that our chromosome
number two is equivalent to two pairs of the chimpanzee's
chromosomes.
1307/ It was accepted
practice to castrate certain inmates in 'lunatic asylums'
in some parts of America until quite recently. These unfortunate
individuals lived on average fourteen years longer than their
intact companions.
1308/ Dolly the 'cloned'
sheep was not really a proper clone as there were traces of
DNA from the original donor egg in her genetic make-up as
well as the DNA of her clone mother.
1309/ Monogamy is rare
in nature. It is most common in birds, where more than 95
per cent of known species are monogamous.
1310/ The sex of a turtle
depends on its temperature during development. At 26 degrees
centigrade all the eggs hatch as males; at 34 degrees centigrade
all are female. Equal numbers hatch only if the eggs are at
about 30 degrees centigrade.
1311/ Studies of baboons
and macaques have shown that sex ratio is intimately linked
to social status. Socially dominant mothers tend to produce
an excess of females, while subordinates favour sons. High-ranking
females amongs the baboons of Amboseli produced ten males
to nineteen females, that is 34 per cent males. Low-ranking
females in the same troops produced 68 per cent males.
1312/ The 1976 census
of Canada showed that a man is statistically more than three
times as likely to die then a woman between the ages of twenty
and thirty. This difference is almost totally attributable
to external causes - accidents, suicides, homicides, poisonings
etc - rather than the internal causes of disease and decay.
1313/ In 1999, a report
from the Office for National Statistics in Britain showed
that young men are three times more likely to die in road
accidents than young women, and that most of the women who
do die are passengers. The particular danger areas highlighted
for men in the report were fifteen to twenty-four and over
seventy-five.
1314/ The Amazon Molly
fish has almost, but not quite, done away with males. The
species is thought to have arisen from a hybrid of two closely
related sexual species. It reproduces asexually, laying unfertilised
eggs that grow into exact genetic replicas of the mother.
No male mollys have ever been found. but the females retain
a curious reminder that the species was once sexual. In order
to trigger the growth of the egg into a clone, the egg must
be penetrated by a sperm. To get the neccesary sperm the emancipated
Amazon Molly has to dupe a male of one of the closely related
'parental' species into mating with her. His genetic material
is then totally ignored in the production of the subsequent
offspring.
1315/ Scientists studied
the seals of Ano Nuevo island for many years. In one season
they watched as five of the 115 males performed 123 of the
144 copulations. In other words, 4 per cent of the males accounted
for almost 90 per cent of the matings.
1316/ Hanging-flies are
small insects that live in the woods of North America. The
male hunts for small insects, but, when he catches one, instead
of eating it he simply holds onto it and uses a special scent
to advertise for females. The female finds the male, who offers
her his nuptial gift. She takes it, and allows him to copulate.
The larger the insect he has caught, the longer it will take
her to eat it, and the longer she will allow him to copulate.
1317/ Mormon church leaders
of the nineteenth century, who had to provide a seperate establishment
for each wife, averaged 5 wives and 25 children. Lesser mortals,
not members of the church hierarchy, could afford an average
of only 2.4 wives and fathered an average of 15 children.
And the unfortunates who could keep but a single wife fathered
just 6.6 children.
1318/ Bobbi Low, of the
University of Michigan, surveyed 138 different cultures as
part of a thesis on ornamentation in the human species. Of
the 138 societies, 99 had a signal that advertised whether
a woman was married or not. But only 4 of the 138 had similar
signals for men.
1319/ A survey of homosexuals
in San Francisco in the late 1970's by A.P Bell and M.S Weinberg
showed that among white males, 28 per cent reported having
had more than a thousand partners, and 75 per cent said that
they had had more than a hundred partners. Not one white female
reported having had a thousand partners, and only 2 per cent
had had more than a hundred.
1320/ The average difference
in height between men and women is about 8 per cent, slightly
less than in chimpanzees. Least different are pygmies of Central
Africa, in whom males are just 4.7 per cent taller than females.
Most different are the Tarahumara, a tribe of American Indians
who live in northern Mexico who are 11.6 per cent taller than
the women.
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