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| The Fight for Love |
July 6th, 2003.
By Professor Fabio Cupul
University of Guadalajara Puerto Vallarta Campus
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When the reproductive season begins,
some species of European male snakes defend their territory
against the imminent invasion of other rival males.
Most of their battles are only symbolic: they “stand”
in an erect position and try to topple their opponent.
The weakest fighter is forced to give up, slither away
and lose the opportunity to mate with the fertile females
of the region. There are no bites in these fights for
love as the venom is meant for killing prey during the
hunts and not for hurting one’s rival for the
lady’s love.
 In
the spring, male elephant seals gather along the beaches
of various islands off the coast of California to compare
strengths until one of them manages to gain dominance
over the entire territory. Only then will the females
begin to arrive on the beaches to give birth to the
offspring conceived the previous year. After 28 days,
when the little ones are about to be weaned, the females
go into heat and mate with the dominant male.
At the end of the mating season,
the main elephant seal on the beach may have inseminated
up to 100 females. In contrast, most of the other males
that could not get a place on the beach will not have
left any descendants whatsoever. Nevertheless, the dominant
male pays dearly for his reproductive and hierarchical
accomplishments as the constant fights and matings,
all done on an empty stomach, deplete the animal’s
strength. He has no time to eat as he spends most of
his time watching over his harem to stop any intrusion
by other males. A truly exceptional elephant seal can
remain the dominant male for three consecutive seasons,
but he usually dies after the second year of his “reign”.
Also, the rhino beetle of Japan is
an extremely aggressive insect that will usually fight
other males of its species for dominance over a reproductive
territory. In their adult state, these little creatures
come out of damp rotten wood. Their size depends on
the amount of food they have consumed during their larva
stage. Large males can measure as much as 7.5 cm. in
length. They have a large horn on the head and another
small one on the thorax.
During the night, the female that
has no horns and measures only 5 cm. in length feeds
on the sap of trees. The males fight for the possession
of those sources of sap, pushing rivals out with their
horns. Little males don’t fight. On occasion,
they may sneak into the females’ area in order
to mate before the big guys arrive. But if the females
mate with the big males afterwards, the sperm of the
latter will displace that of the smaller.
 The
males of one species of African antelope have two strategies
to choose from in order to find a mate. Some defend
great territories where food is plentiful and they can
mate in relative safety with the few females who come
there to eat.
On the other hand, those who are
unable to acquire extensive territory gather in a sort
of arena where they show off their abilities and strengths
before visiting females. Here, every male has its own
small territory which he defends ferociously. Those
spaces can measure up to 25 meters in diameter (75’)
and they do not have abundant food within them.
This technique can give good results
as the stronger, more competitive males can mate with
various females. The disadvantage is that the frequent,
extended fights to defend a territory with little food
can become exhausting for both sides.
Furthermore, one runs the risk of
being seriously wounded and dying at the claws of a
predator. For example, hyenas watch the fights and attack
the more exhausted male as soon as he tries to take
a rest.
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