Author: Sterling
Title: Maximizing Fitness
Summary: Don't read this; you won't like it. Well, a few people
might. It's pretty cerebral and there's no dialog to speak of. A
land of islands has a slightly different species of humans. There
are only a few men, and they engage in more matter-of-fact
killing than sex to further their Darwinian genetic fitness. I
trace the life of the man Buck and explore in detail why he does
what he does -- and why the females do what they do.
Keywords: Mg Mf MF het cons coercion violent first preg SciFi

NOTICE:  This story contains explicit sex.

First posted 4/6/2011.

I'm always eager for comments, whether good, bad or mixed.
Comments to sterling27@live.com.

I have written many other stories and they can all be found at
/files/Authors/Sterling/

You are welcome to copy this story if you include the entire text
unchanged, including this notice.  If you tell me where you have
re-posted it, I can enjoy knowing it is appreciated and perhaps
enjoy the feedback the story gets where you re-post it.

Sterling

And now, our feature presentation.  Enjoy!

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Maximizing Fitness

Buck knew that his quest was very dangerous; he would probably
fail and might well be killed. But he couldn't resist. He he was
driven to maximize his reproductive potential by fathering as
many children as possible.

The females on his own islands were all impregnated. One option
was to lie back and defend his own, leaving more offspring as he
mated with his girls when they came of age. But if he could take
over another island, if he could get lucky and kill the ruling
male, then there would be more girls to fertilize, and the
prospect made him smile as his loins stirred.
 
He could leave far more new descendants, perhaps 5 times as many.
So even though his chances of dying were perhaps 50-50, he would
on average leave more descendants by taking the risk than playing
it safe. He didn't think of any of that, of course. But those
were the evolutionary pressures that had shaped him. He was
descended from a line of males who had been inclined to take the
risk, and their genes had elbowed out those who like playing it
safe. Those men may have grown old rather than dying young, but
that didn't matter.

Those same genes were present in the other men on islands
surrounding his. From time to time one of them would land on one
of his islands and he would drive the intruder way or
occasionally kill him. He knew every inch of his islands well,
and he got a little help from his women -- not much, but so far
it had been enough.
 
He often dreamed of an expedition and the females he might find,
but what stirred him to act now was that he had just killed one
such interloping man two days before. He didn't know what island
that man came from, but no male would come from that particular
island for quite some time; a new man would have to establish his
dominance there first. If he picked the island that the man came
from, his chances of dominating it were excellent. What's more,
none of the men on other surrounding islands knew that the master
of an island had just died, so the chances were no higher than
usual that they would make a play for one of his islands just
then.
 
He had to decide which island to visit. He decided on the one to
the east, just visible on the horizon. His own three islands were
close enough together that he swam from one to another
frequently, but this would be a long swim.

He set off with his weapons -- a knife and bow and arrows -- in a
harness on his back. After the daylong swim he lurked offshore,
keeping as low a profile in the waves as he could. If he was
spotted, he hoped he would be mistaken for some floating debris.
He scanned the island as the afternoon grew late, trying to
memorize the features. He saw only an occasional sentry, which
heartened him.

Soon after the tropical sun went down and dark fell, he swam the
last little bit of his journey. It was a moonless night, also
part of his timing decision. He didn't want to land on a beach,
nor did he want to land on a rocky point. The beach was easy for
a sentry to scan, and the point was obvious enough that it would
warrant special attention. Instead, he chose a rocky shoreline
not too far from the point. His heart pounded as he rode a wave
in and found a purchase on a rock. He clambered up over the rocks
quickly, earning a painful gash on his shin. He moved quickly to
keep from being pounded by another wave, but more importantly to
reduce his exposure time. On those rocks he was at his most
vulnerable and he half expected that a woman would be even now
running back to the man of the island so he could ambush Buck at
a time and place of his choosing.
 
But he made it into some dense foliage, where he could rest and
regain his strength after the long swim.
 
After a couple hours of rest, he started walking inland, trying
to make as little noise as possible.
 
He saw her before she saw him, and that made all the difference.
 
The forces that shaped her to maximize her fitness were very
different from Buck's. If she could raise the alarm without being
killed herself, the man of the island would very likely kill Buck
or at least force him off the island again. That would prevent
Buck from killing some of her relatives whose lives were in
danger if he succeeded in his mission. But if she herself was to
die while sounding the alarm, that was a more serious downside
because she could then of course bear no further children. She
knew that with him this close he would kill her if she shouted --
his genes were shaped to do that precisely to deter her from
sounding the alarm. Her hope was to follow him quietly so he
could tell she was not alerting anyone else, and he might let her
live, for instance for information she could give him.
 
Instead of shouting or trying to run, she turned and stuck out
her rear end to Buck, showing she was available for mating
whenever he wanted. 
 
Buck dimly made out her rear end in the starlight, but he had
different plans for her. There is genetic diversity. Many men
would have let her tag along behind him, and her genetic gamble
was that he was one of those men. But he was not. She still might
give him away in some fashion. He came up behind her and grabbed
her hips as if to mate. Then suddenly he put both hands around
her neck and squeezed hard. Now it was in her genetic interest to
shout if she could. She herself was doomed but by alerting the
island she could save some of her sisters. By the same token, it
was vital to him that she not make any noise. She thrashed, but
he was much stronger. Within a couple minutes her feeble
movements ceased completely. He waited a little longer for good
measure, then turned her over onto her back and slit her throat.
It was the first of a great many killings to come.
 
Buck could have tried to get her to answer some questions before
revealing that he was going to kill her, but that too had risks,
a major one being that she might lie.
 
He crept carefully along what seemed to be a path. Soon he saw a
glow not far ahead and heard the murmur of voices. He moved
forward even more slowly. He could glimpse the fire through the
trees, and worked off the path to one side. Surely a sentry would
be guarding the path. Shortly after he left the path he saw her
right next to the path -- she would have spotted him if he had
gone forward another twenty yards.
 
He crept to a spot thirty yards from the center of the settlement
with an unobstructed view; some women and girls were around the
fire. He now took out his bow and arrows. He had spent a great
deal of time choosing the materials for this bow and crafting
them -- it was vital to his reproductive chances at a moment just
like this.
 
After making sure he had room to draw the bow and aim properly,
he sat down to wait. Now he needed the man to appear. As the
hours went by, the women and girls headed off to bed. Buck was
sorely tempted to sleep, but he kept waiting. The fire burned
low.
 
The approaching dawn shaded the sky from black to gray.

He saw him then, emerging from a hut sleepily, a large man with a
head of graying hair. He was perhaps forty yards away. Buck felt
a thrill. His aim when firing this arrow could mean dozens more
descendants for him and dozens fewer for the man. The man yawned,
shook his head sleepily, and then stretched, raising his arms
high in the air. His exposed chest made a fine target. Sexual
pleasure tingled within Buck as he fired. His first shot missed,
and the man came down out of his stretch, perhaps having heard
the arrow whiz by. But before he had time to react, Buck's second
shot caught him squarely in the chest. After looking around in
panic, the man fell with a groan.
 
The long wait was over, but now Buck had a great deal to
accomplish in a short time.
 
The sentry was almost certain to be one of the women he would
want to kill, and since she might conceivably be armed, he
delivered his third arrow into her as she dozed. She let out a
little cry. He raced towards her. Quickly unsheathing his knife,
he turned her onto her back and slit her throat.
 
From there he raced into the clearing. His first stop was his
rival, who lay looking at him groggily. There was no need to give
a victory speech or hear the man's last words. He simply slit his
throat and watched briefly as the blood gushed forth. If the man
had caught Buck on his own island, he would have done the same
thing.
 
The first few women who appeared from their huts screamed when
they saw Buck standing with his bloody knife.
 
Then the carnage began. Some of the women and children raced out
of camp. As fast as he could get the arrows into his bow, he
fired at the fleeing women. He hit only a few women, but had a
bit more luck with the children.
 
Only some of the women left. Others, especially women with young
girls, stayed and approached him, and he was careful not to shoot
them. He was delighted to see girls as old as eight had stayed.

-------------------------------------------------------------

Buck's emergence as the new man had complicated genetic
consequences which would take some time to sort out. But in
general the women who had run from camp were programmed by
evolution to run because they knew that death awaited them in the
camp if they stayed. Buck himself could not tell why, but the
fact that they wanted to get away was itself a sign that they
needed to be killed if he was to maximize the number of his
offspring.

It was to their advantage to run because many of them managed
their escape and might yet live.

The ones who stayed believed that Buck probably would spare them
after he had examined them and pondered the situation.
 
The fact that girls as old as eight remained was a good sign. It
meant that for whatever reason the old man had not mated with
them yet. They were virgins, and their reproductive potential was
his for the taking. The reason was simple and easily confirmed
when he asked the women: the man had been totally impotent for
the past four years.
 
The social structure of the islands had molded the behavior of
men and women alike, but it had also molded their physiology.
Since there were very few men and they killed each other
frequently, sometimes years went by with no virile male in sight.
The women had evolved the ability to store sperm for years.
Whenever their bodies were ready to bear another child, a
hormonal signal awoke a small number of the sperm from suspended
animation, and they wriggled to the egg and fertilized it.
 
In a parallel development, the men had evolved large testicles
and ducts to hold a great deal of sperm. Their bodies were
adapted to produce large quantities of the other components of
seminal fluid very quickly.
 
Another development of equal genetic interest to male and female
alike was that the man would mate with young girls, whose vaginas
matured correspondingly early. They could store his sperm as well
as their mothers could, and even if they wouldn't need any for
years, the supply would be ready when the time came. If no other
man appeared in the interim, it was very much to their advantage
to have the sperm to reproduce rather than remaining childless.
 
In that the interests of male and female coincided, but in
another way they did not at all. An evolutionary battle raged
within the reproductive tracts of the females. The man's interest
was to claim all of the woman's future potential for himself, to
arrange so future ejaculations inside the woman's vagina could
not compete with the sperm he had already deposited. But while it
was in the woman's interest for a man's sperm to last a long time
within her reproductive tract, it was very much in her interest
to allow a new man's sperm to compete or -- preferably --
supplant the earlier man's sperm. At the moment the battle
favored the males' interest, though not completely. The first
ejaculation inside a girl's vagina triggered biochemical changes
that prevented further sperm from taking hold.
 
As the usurping male, Buck at the moment shared the genetic
interest of the women. But it was the initial ejaculation of the
old man long before that had made the women's bodies resistant to
conceiving babies with fresh sperm.
 
A number of factors influenced which females Buck would kill.
Being pregnant was at the moment bad for her. Not only would she
give birth to a baby who was not Buck's, he wouldn't even have
the chance to try fathering a new child with her for some time.
The younger a girl who was not a virgin, the worse for her. The
previous man's sperm was copious and fresh, and the biochemical
defenses against his sperm being able to gain a foothold were
strong. As the women aged, the defenses wore down and Buck's
chances of impregnating them with his own sperm went up.
 
This was one reason why some of the older women stayed in camp.
Since Buck would have a fair shot at impregnating them, he might
not kill them. The stronger reason was that they were the mothers
or grandmothers of the girls aged eight and under. It was in both
their interest and Buck's to protect and provide for those girls
as they grew up and bore their joint descendants.

As noted before, there is genetic variability. Buck might have
spared some of the women who fled, but their gamble was that he
would not. He might kill some of those who had remained, if his
calculus was a little different from the women's.
 
Shortly all the women and girls had made their initial decision.
Many had chosen to flee, and some of those had been shot down and
methodically dispatched by Buck. Others had chosen to stay.
 
Buck's fitness commanded that he begin his inseminations at once.
His balls were full of sperm. It was also in his interest for the
women and girls to see him mating with the girl, showing them
that he was virile. If he had been sickly or had trouble with
performance, some of those girls and their mothers might have
slipped away into the woods to take their chances.

If a man took a girl's virginity but did not impregnate her
properly, her future was dim. Another interloping male would be
likely to kill her instead of trying to plant his own seed, and
if no new man came at all she couldn't reproduce either. They did
have some hope, though.
 
One of the girls who remained was apparently in that exact
position and clinging to that hope. If Buck examined her and
determined that she was definitely past the age where she would
have borne her first baby and yet had no enlarged nipples, no
stretch marks on her belly and a tight upper vagina, it would
suggest that the other man had not been potent. His biochemistry
might have locked the girl's loins against impregnation by Buck
-- but it might not. She would not bear any of the other man's
offspring, and she would either bear his or bear none at all --
which was no big loss to him.
 
But Buck was going to work first on the virgins. "I'm going to
fuck her," he said, pointing to the oldest of those girls who had
not fled and stripping off his homespun shorts. Blood pulsed into
his penis and he was erect in seconds.
 
"Good girl!" whispered her mother, who quickly helped the girl
out of her homespun dress, leaving her naked. "Be nice to the
man. Do everything he says, OK? Treasure the moment!"
 
The girl nodded, but looked anxious.

"Hands and knees!" Buck said.

He knelt behind her and began by taking a very close look at her
genital region. He wanted to make sure she really was a virgin.
It was harder than one might think, because the girls had an
enormous genetic advantage in looking like virgins even if they
weren't, and their physiology was influenced accordingly. Just
because she had not fled was no guarantee she actually was;
another route to her survival was for him to conclude she was a
virgin when she wasn't. By examining her folds carefully, he was
convinced that no penis had been there before. This brought his
cock to peak hardness, and with excitement he brought himself up
behind her and brought his cock to her feminine opening.
 
He poked gently at her opening over and over, and her juices
flowed. When he sensed that her tract was lubricated, he slid
inside. As he penetrated her, he attended to the tightness on his
penis to continue his diagnosis of her virginity, and it
confirmed his judgment she was. She also gave a yelp. The fact
that the penetration hurt was no concern of his. Back and forth,
deeper and deeper he pressed. Within a few strokes the girl
started sighing and gasping, obviously very happy. That was no
concern of his either.
 
Buck's penis was long, far longer than was healthy for these
young girls if fully inserted. He carefully limited the depth of
his intrusion to avoid damaging his young girls. The length of
his penis was for another purpose.
 
The girl might never mate again. Her lifetime sexual pleasure
might come from this one act. Her orgasm started after a few
strokes, and with every movement of Buck's penis in and out it
was prolonged. Her ecstasy was indescribable, unlike anything she
had felt before and anything she would ever feel again.

He was about to do his very favorite thing in the world. He felt
his cock swell, felt his tubes and tracts inside shifting, and
then ecstasy took hold of him as he began his ejaculation. His
first three shots of semen rocketed into her upper vagina,
immediately starting to loosen her cervix. His physiology had
evolved so he didn't deliver his next shot right away. It was ten
seconds before his cock fired again, and more semen filled her
female tract. Her body needed time to absorb the first shots
before it could handle the later ones. From the start of his
ejaculation he stayed coupled to her for a full two minutes,
every ten seconds another splat of high-quality sperm delivered
up the cunt of the girl who knelt in the stupor of continuing
orgasm.

One purpose of her continuous orgasm was the uterine
contractions. They were a significant help in pumping all of
Buck's sperm deeper into her body, The other purpose of the
orgasm was to provide the hormonal signals to awaken her sperm
storage system.
 
Finally, profoundly satisfied, Buck pulled out and lay back on
the ground to catch his breath.
 
"Here, honey, lie on your back," her mother said after Buck
uncoupled. "Keep as much of it up inside as you can."
 
Helped by her contractions, the sperm swam up through her uterus
and through her Fallopian tubes. Most of it went and burrowed
into her ovaries. As Buck's organ kept pulsing, sperm swam
through her entire body cavity. There was no benefit to this, but
evolution hadn't eliminated it -- Buck's sperm was relatively
cheap in evolutionary terms. Most of it flooded into her ovaries,
where it became dormant.

When she became fertile in a few years, some of the sperm would
awaken at the chemical signals given off by the egg, and they
would fertilize it. She would become pregnant with his baby. As
soon as that one was born and her body was recovered enough to
produce the next egg, a little more sperm would wake up for that
one too. He was impregnating her for life. She could bear twenty
children, but would never have to have sex again. This one act
was all it took to meet her every reproductive need.
 
The remaining women immediately began grooming their young
daughters to present them in the most alluring fashion possible.
They vied to pamper Buck. They served him delicacies and
protein-rich food to help with his sperm production. All were
hoping their daughter would be next.

Buck took another little girl the next morning, dipping into his
sperm reserves. He left time between matings to allow his fluids
to achieve full potency.

Then he went hunting. He would alternate hunting expeditions with
fertilizations.

-------------------------------------------------------------

Buck's ability to move silently through forest was key. The
thoroughness of his hunt would have a large impact on his genetic
success.

His first hunting session was productive. Many of the girls and
women who had fled were not very good at hiding. If he found a
woman alone or with children, he would charge her. She would run
if she had any time. He caught up to her, tackled her, and sliced
her throat cleanly. He then took off after her children. Their
lower speed made it less likely they could escape on foot, and
their smaller size gave them a better chance of hiding, so that
is what they tried to do. Instead of wailing for their mother,
they were programmed to remain silent. But these adaptations were
a desperate measure. He generally found them and killed them, one
by one.

He was especially attentive when he saw boys. Ordinarily the old
man wouldn't have allowed any boys to survive, but because of his
impotence, he had been inclined to let a few live. As long as he
was virile, it was to his advantage to inseminate all the females
himself, but his sons also carried half his genes and could mate
with his daughters when they grew of age. Some other man such as
Buck was less preferable as a father because he shared none of
the man's genes, and in any event there was no guarantee that
another man would arrive soon. There would have been a gap when
no mature male was available to breed the females. In this case,
the gap began with the onset of his impotence. It would have
ended when the first baby boy who was allowed to live reached
puberty and beyond. It wasn't good to have this be too long a
gap, so the old man had allowed a few boys to survive. It was
unlikely that it was a conscious decision -- that's just what the
old man's instinct told him to do. However, Buck's arrival
rendered all this planning moot.

After two days of hunting and over twenty killings, he returned
to his camp. The women fed him more high-protein food, and he
ejaculated his copious loads of semen into the girls, one by one.

There was a reason he mated with a girl once and gave her a large
dose of semen instead of counting on multiple matings. The very
same mechanisms that deterred other men's sperm from fertilizing
the girl also made his own later ejaculations largely
ineffective. He had one main chance to impregnate her -- one
sexual act. He needed to deliver into her vagina many large blobs
of thick semen, all teeming with high concentrations of his
sperm.

As the days went by, Buck was delighted mating with the girls,
pulsing his seed deep up the pussies of dear little things as
young as four years old. Mating with girls younger than that
wasn't to his advantage, since the risk of damaging them was
greater than the risk of their being bred by another man. Chances
were he could come back at least once a year and breed them
when they came of age, one by one.
 
Now Buck examined the older girl who had stayed. He slid his
finger into her vagina and explored, as the girl presented
herself with anxiety. Her upper pussy was tight. Her nipples were
small and unused; no baby had nursed on them. The girl was
visibly relieved when he fucked her instead of killing her,
delighted to get his massive dose of sperm. She was happy for him
to repeat it over and over. The alternative was death.
 
-------------------------------------------------------------

His mating was an unqualified joy.
 
Finding refugees in the hills was harder, though. The ones he had
not found so far were better at hiding, and his chances of
finding them later if he hadn't succeeded at first were low. In
some cases they had escaped from sheer luck, though, and he had a
good chance of finding and dispatching them.
 
He had one especially important encounter. From far off he saw a
person who looked bigger than a child. As he worked his way
closer, he caught sight of the person again. He was an adolescent
boy! He was a grave threat to Buck's reproductive success. If he
achieved adulthood, he could kill Buck as he tried to approach
the island again. When he came to produce semen himself, he could
impregnate the little girls that Buck might not get to this time.
In time he might even start killing off the girls Buck had just
now mated with.

He put himself in the shoes of an adolescent boy who had
undoubtedly overheard from the panicked women that the old man
had been killed and a new one had replaced him. This was bad news
for the boy, who had had a strong possibility of simply waiting
until the old man died and then taking over the island for
himself. He should know instinctively that the new man would be
hunting him, so he would need to be vigilant, and hopefully kill
him before he was killed. His vigilance had been ineffective to
the extent that Buck had detected him.
 
Buck's first reaction was to make a point of staying out of
sight. The boy would have weapons and if his genes were true he
would try to kill him. Having once demonstrated his virility,
Buck didn't need to mate in public. He hid in areas away from
camp and got mothers to bring their daughters out to him for
their mating. 
 
Where would such a boy live? One side of the central hill had a
small area of volcanic rock that had been shattered, leaving
boulders and caves. It looked to afford the best hiding places.
Buck spent two full days watching from a distance, and was
surprised to see a second boy appear briefly. Having two
adversaries made his job more difficult. These boys were
undoubtedly armed, and trying to invade the area of boulders and
caves was a high-risk proposition.

But he developed a plan. He finished inseminating all the girls.
Although he had plans for more, he had done enough that the women
would not think it was strange for him to leave.
 
He announced his departure. A few of the women saw him stash his
weapons in his harness and swim off over the horizon. But once he
was out a mile or so, he stopped and waited. Under cover of
darkness, he approached the island again and came ashore at a
different spot. He silently approached the hillside where the
adolescent boys lurked, and he waited.

He expected that the two boys would have learned of his departure
by careful observation if nothing else -- the women and girls in
the village could now go roaming into the woods without fear of
being mistaken for Buck's genetic enemies and killed. He hoped
the boys would let their guard down and come to investigate.

He smiled as he saw the two boys leave their refuge high on the
hill. He decided to go into their lair and wait for them to
return, when he could dispatch them at close range. He approached
the lair carefully, and it was a good thing. As he scrambled over
a last boulder, he saw a third boy! Had the boy detected his
approach, Buck's life could well have ended with an arrow in his
chest. But Buck's stealth had been enough to get him close to the
boy before discovery. The boy lost precious seconds stunned by
the surprise appearance of the man. Had he retrieved his knife
from several feet away, it would have been riskier for Buck. But
as it was Buck was upon him, wrestling him to the ground, pinning
him, and then stabbing him in the back repeatedly before slicing
his throat open for good measure.
 
Had there been a fourth boy, he probably would have dispatched
Buck with his bow and arrow. But Buck's entire venture was risky,
and he got lucky. There were only three boys.
 
The fact that there had been three boys was interesting in
itself. Eventually, one would kill the other two unless they
managed to leave the island. Perhaps evolution dictated that the
three of them working as a team could help each other enough that
it was not yet worth their while to kill the other two, but it
was obviously an unstable situation.
 
He then waited for the other two boys to return. As it was, the
two approached side by side, laughing and joking. This lack of
vigilance betrayed genes that would be culled from the gene pool.
Buck waited until they were 10 yards away and launched an arrow
straight into the chest of one of them. If the other charged,
Buck was prepared to drop his bow and take up his knife. As it
was, the second boy chose to run. Buck had time to fit another
arrow into his bow and shoot the boy in the back. The
boy stumbled but kept upright, and Buck needed a third arrow to
bring him down. As usual, he slit their throats to make sure they
were really dead.
 
His most serious rivals were out of the way, but his stealthy
second landing had another benefit. As he approached the main
camp, he saw a mother and two young sons who he didn't recognize.
They had returned to camp when they heard Buck had left. He shot
the mother with an arrow and the two boys of course had no
chance.

"His" women were surprised to see him return. He would continue
to hunt during the day, and he would resume his inseminations.
 
This time he turned his sexual attention to the adult mothers.
One by one he took them and fucked them from the rear. He did
them hard, and he made sure to get the very deepest penetration
he could. The women yelped and cried. Roughing up their vaginas
gave Buck a greater chance of overcoming the previous man's
barriers against his sperm. Buck didn't know that -- he just had
an impulse to fuck those women hard. Evolution had selected for a
long, hard penis for exactly this purpose. He used shallow
penetration with the tender young girls, deep penetration for the
women who had been previously inseminated.
 
Although the women could see that the others were in pain from
Buck's intrusions, they still encouraged him to fuck them too.
Any evidence they gave that they did not want to bear Buck's
babies was an invitation to be killed. Vaginal pain, even if
severe, was far better than death. Buck's rough treatment
increased the risk of infection or genital harm that would make
them infertile. That too was a risk they would have to take.
 
Buck mated with them over and over again, always aiming for that
extra chance at impregnation.
 
After he had spurted his semen where it had the greatest chance
of fathering a child, he took to a bit of recreational sex while
his sperm supply was low. He mated with his little girls again,
pulsing their vaginas with semen once more. It had a tiny chance
of helping activate the defenses in the girls against another
man's sperm. It also just felt awfully good. Not every aspect of
human behavior has been shaped by evolution.

He stayed two weeks after he killed the adolescent boys. His
hunting expeditions had bagged him no further human game, nor any
sign that other refugees remained. There was some chance that
more hunting expeditions would locate more refugees, but he had
reached the point of diminishing returns. Maximizing his fitness
called for him to move on.
 
Buck had engaged in a great deal of killing. The population of
the island was perhaps a quarter of what it had been. But what
mattered to Buck from a genetic perspective was that as the
population grew again, most of the new babies would carry his
genes.
 
And what did the women think of this slaughter? They were used to
boys being killed routinely in any event; that was just part of
life. What about the slaughter of their sisters, mothers, aunts,
nieces, and daughters? They were sad, of course. But they didn't
take it out on Buck. He was just doing what any male would do.
Their genetic future lay with cooperating with him and helping to
replenish the island's population. The new babies would bear
Buck's genes, but they would also bear their own.

Their chance at avoiding the slaughter had lain in an effective
sentry system to alert the old man when Buck first landed. But
vigilance every day and night for years at a time is expensive
too, in terms of lost time gathering food. The man's impotence
may also have contributed to less vigilance on the part of the
women.
 
-------------------------------------------------------------

Buck had a strong temptation to return to his own islands at
once. He had been away for a long time and his domain lay open to
attack.

But he also had that urge to go on, to find more of those young
girls. One island was clearly visible on the horizon, and after
his long swim Buck approached at night as before.
 
He encountered no sentries. Still, he approached the camp
carefully. There was no man present. This didn't surprise him
especially -- if an interloper chose this period of Buck's
absence to invade one of his home islands he would find no man
there either.

When he made his presence known, the women were very anxious. A
few headed for the woods by instinct, and following his own
instinct he killed two as they tried to flee.
 
He was surprised to see very few children. The youngest children
were about twelve years old, all girls. None of them were
virgins, which meant his instinct was to kill them, but something
held him back. Soon a young woman explained that the last man had
been there eight years before, and had as expected killed all the
boys and all the older girls. The only fertile females he left on
the island were those between the ages of about four and twelve;
he also left a few older women. That was all standard. What was
highly unusual was that while the surviving girls now ranged in
age between twelve and twenty, none had become pregnant.

Although driven by instinct, Buck also had reasoning power. He
decided that the man was infertile! While undoubtedly he had
ejaculated gobs of semen up inside the vaginas of all the girls,
it hadn't done any good! Buck got a description of the man, and
it was clear it wasn't the same man Buck had killed.

Why the man Buck had killed had not been to this neighboring
island as it sat open for the taking wasn't obvious. Perhaps he
had had a different survival instinct. Instead of approaching and
attempting to take possession of this island, he had just sat
back on his own -- which was admittedly a rather large and
fertile island. Another possibility was that through some
combination of age, injury, or genetic endowment he was not a
great swimmer.

So Buck fertilized all the females on the island, taking a couple
weeks for the process. Mostly they got rough treatment as he
stabbed his penis into them all the way and jabbed hard before
ejaculating. The man had been infertile, but he might well have
had the chemical triggers it took to shut out Buck's sperm. These
were no longer little girls; a vagina in a twelve-year-old was
able to take more punishment than that of a four-year-old.

Buck's hunting expeditions were much less intense here and had a
different purpose. When he found a couple young women on his
hunting expeditions, they were naturally terrified. But he didn't
kill them; he instead brought them back to the camp and mated
with them. Hunting was less important because while any girls he
missed wouldn't bear his children, they at least wouldn't bear
those of any other man either. And there couldn't be any other
males on the island.
 
He thought he could see an island on the horizon further east,
but his decision in this situation was clear. It had been a
questionable move to come to this island at all, but now his
interest lay in heading back west to his own islands. With his
two new conquests he now had five islands configured to his
genetic advantage. His judgment, deriving no doubt from natural
selection in his past, was that he must try to defend what he
had. His expedition had taken him over two months. He returned to
the west, past his other newly conquered island to his main
three.

A tragedy had struck. A man had been to his northernmost island
in his absence, and the island was nearly depopulated. There were
only a dozen-odd girls under the age of six and half dozen older
women that the man had intended to leave. Naturally he had
slaughtered all the girls that he, Buck, had impregnated, and
left only those that had been too young for him to breed. But the
intruder's hunting had not been so thorough. Buck was heartened
to see that another dozen women and girls whose innards teemed
with his sperm had survived.
 
Buck spared the two three-year-olds the other man had
impregnated. The other man's calculus apparently called for
breeding girls on the younger side. This made sense if he thought
he was unlikely to be back to breed them. Perhaps he, too, had
been marauding far from his home base. It was possible that those
girls were too young for his sperm to survive at all and too
young for his chemical signals to shut out future sperm. Buck
would be back to plant his seed when they were a little older.
There was also the fact that those girls were his daughters. Even
if the other man had bred them, they still carried a quarter of
his genes.
 
--------------------------------------------------------------
 
Buck swam among his islands. Now and then he decided a girl of
around four had gotten old enough to be bred. He killed all the
baby boys, just as everyone knew he would.

Two years passed.
 
Because of the long swims required he didn't get to his
easternmost island as often as he would have liked. When he
visited after a four months' absence, he wasn't careful enough.
Another man had arrived in the interim. Buck was himself felled
by an arrow from a man he never saw -- until he approached and
matter-of-factly slit his throat.
 
Trying to hold five islands was very perilous, and it was
surprising Buck had lasted as long as he did.

Buck's killer was halfway through the carnage when Buck arrived,
and he of course finished what he had started -- that was the way
of the world.
 
Buck's killer as a young man, barely out of adolescence. He had
decided to flee from his own island, where two other boys of
roughly the same age were trying to kill him as they fought to
establish their dominance of that island. The young man's
judgment was that trying to take a new island was less risky than
staying. His gamble had paid off. Now his interest lay in staying
on the island as he grew to his full size and strength. In the
interim he would improve his archery skills and equipment and
practice swimming. Now and then a young girl would need breeding.
And there was plenty of time to mate with any of the women who
struck his fancy. He would not be rough with them, however, since
they already had his sperm and he was not trying to compete with
another man's seed.
 
On Buck's other islands, there would be a time of change. Buck
could no longer kill the baby boys. As a half dozen years passed
without another visit from Buck or another enterprising intruder,
the women would decide it was likely that the new master of the
island would come from among the boys of the island. As the boys
approached adolescence, a time of chaos would ensue. A few
mothers might surreptitiously murder each other's boys. As a
precaution, the camp would fragment for a time, each small group
of mothers protecting its own. When the boys reached adolescence,
they would engage in scouting trips and kill each other, as well
as the younger boys who were still being born to the women of the
island. In time one would kill all the others unless they chose
to flee and try their luck elsewhere.
 
The new young man coming into his own at age 15 would inherit a
world where all the girls under age 19 were virgins, and he would
have the pleasure of inseminating all of them. The women who were
20 and above were all pregnant with Buck's children. He would
follow his instinct and brutally fuck them over and over, hoping
to overcome Buck's barriers. But he would not kill any. Their
children were at least his half-brothers and sisters, and some
had closer relationships.

 
After one male came to dominate each of Buck's former islands,
the pattern would repeat itself. The between-island raids would
begin. One young man might succeed in taking over his neighbor's
island; more likely he would be killed and the surviving neighbor
would then have a shot at the intruder's island.

Over time, evolution would continue honing the instincts of the
women and men as they constantly strove to maximize their
reproductive fitness.

============================================================

What did you think? The adaptation arguments are warped a bit in
the interest of making a good story, but they are meant to be
reasonable. Feedback on them and any other aspect of the story
would be much appreciated. I'm always eager for comments, whether
positive, negative or mixed. Comments to sterling27@live.com.