GOOD PARENTING PART-1
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[Figure1. This figure, though looks
clumsy, is a really very simple depiction of the different periods of life.
From the mother’s womb to last day of life lesser period is being controlled
and possessed by the parents. Compare the red areas. Note that the time-spaces
shown in this figure are arbitrary.]
PART-1
By the statement, “Are you sure your child
is really yours”, I do not intend to hurt your morality, but want you to think
seriously how long and how much a child belongs to their parents in respect to
outside world. The period of life of a person covered and controlled by the
parents are much less compared to the period exposed to the society. When a
young man in any institute does an unwanted act, the people blame that man and
not his parents. When a person does an excellent job, people reward him and not
their parent. The dacoit Ratnakar had to face the consequences of his sinful
acts, and neither his parents, nor his wife were ready to share those. So, the
child/man has to carry his own life and face whatever the he does. But
basically, most part of his character is inherited from their parents.
I firmly believe that a tiny kid in a house
does belong entirely to the parents. They just a caretaker for the baby and it
is obligatory duty of the parents to bring him up in such a way that today’s
baby is handed over to the society as useful member of the society. This can
only happen through proper parenting. Unfortunately nobody thinks in that way.
The parents often become so much possessive that they ignore the role of the
child’s contributions, good or bad, to the society in future.
Is parenting the only factor in man-making:
do other factors not have influences:
Nobody can deny that other factors affect
the process of man-making. But I am convinced that there is a distinct
difference of the effects of other influences over good parented and bad
parented individuals. A person who is brought through good parenting never has
strong and permanent effects of ill-influences of the society. Even he is
temporarily misled by the bad effects, he quickly gets self-realization, and
not only returns to the right path but also spread rays of moral values to his
associates. Getting tempted for the prohibited acts is a natural instinct of
human. But a true human do not loose himself dark paths very long. On the other
hand, the parson who has been parented poorly always tends to go to the evil
paths quickly. And most of the times this happen permanently and
irreversibly. The person not only puts himself in field of antisocial, but also
tries to influence others. Their influences affect the poorly parented persons
and thus gradually the numbers of antisocial increase.
The parenting is so important that it forms
the base of the individual. A man with a strong base never gets moulded by
external bad influences. Rather through their communications, dealings and
actions try to benefit the society which one can never expect from weak-based
person. Good parenting is thus the corner stone of an individual’s life.
A General Overview of Parenting
Before going to the discussion of methods
of parenting, I like to mention something less discussed like parental
investment.
What is parental investment:
Humans are basically animals with all their
natural characteristics. Like all animals, humans also have to expend, better
coined with the term parental investment.
In iteroparous species, where
individuals may go through several reproductive bouts during their lifetime, a
trade off may exist between investment in current offspring and future
reproduction.
What is
Semelparity and iteroparity? There are two types of species in
relation to the reproductive strategy of an organism. A species is considered
semelparous if it is characterized by a single reproductive episode before
death, and iteroparous if it is characterized by multiple reproductive cycles
over the course of its lifetime. This is comparable to the
terms monocarp and polycarp of plant kingdom.
Trivers (1972) originally defined the
term parental investment to mean any “investment by the parent
in an individual offspring that increases the offspring's chance of
surviving, hence reproductive success at the cost of the parent's
ability to invest in other offspring” Parents need to balance their offspring's
demands against their own self-maintenance. This potential negative effect of
parental care was explicitly formalised by parental investment. Parental
investment is not the cost of raising a child i.e. the money spent for
purchasing tin-milk etc. It means the time and energy the parents have to
invest producing a child and make him survive and grow.
Theoretically, females invest more energy into producing child, This is
elaborately discuss by Bateman, known as Bateman's principle.
Bateman's principle is the theory that
females almost always invest more energy into
producing offspring than males invest, and therefore in most species
females are a limiting resource over which the other sex will
compete. It is named for English geneticist Angus John
Bateman (1919–1996).
According to Bateman's principle, typically
it is the females who have a relatively larger investment in
producing each offspring. Bateman attributed the origin of the unequal
investment to the differences in the production of gametes: sperm are cheaper
than eggs. A single male can easily fertilize all a female's eggs and
she will not produce more offspring by mating with more than one male. A male
is capable of fathering more offspring if he mates with several females. By and
large, a male's potential reproductive success is limited by the number of females
he mates with, whereas a female's potential reproductive success is limited by
how many eggs she can produce. This results in sexual selection, in which
males compete with each other, and females become choosy in which males to mate
with. As a result of being anisogamous, males are fundamentally
promiscuous, and females are fundamentally selective.
Bateman's observations came from his
empirical work on mating behaviour in fruit flies (Drosophila
melanogaster). Bateman hypothesized that male reproductive success increases
with number of mates, whereas female reproductive success does not. He believed
that this hypothesis could be supported by illustrating the variance in number
of mates between females and males, and by plotting reproductive success versus
number of mates.
To test this observation, Bateman crossed
virgin parent fruit flies that were each heterozygous for a unique dominant
mutant phenotype. He placed 3–5 flies of each sex in milk bottles for 3–4 days,
allowed the females to lay eggs, then removed the parent flies and counted the
offspring once hatched. Because most (75%) of the offspring expressed the
phenotypes of one or both parents, Bateman deduced how many mates each
individual had by observing the offspring’s mutations. He judged reproductive
success by counting the relative number of offspring sharing each parental
phenotype (Bateman 1948). Bateman concluded that
a) the
variation in number of mates for males was greater than for females, and
b) 2)
"The males show direct proportionality between number of mates and
fertility... The females, provided they have been mated with at least once,
show absolutely no effect of number of mates" (Bateman 1948)
Bateman concluded that:
A female can have only a limited number of
offspring, whereas a male can have a virtually unlimited number, provided that
he can find females willing to mate with him. Thus females generally need to be
much choosier about who they mate with.
A male can easily produce sperm in excess
of what it would take to fertilize all the females that could conceivably be
available [...] Hence the development of the masculine emphasis on courtship
and territoriality or other forms of conflict with competing males.
In most animals the fertility of the female
is limited by egg production which causes a severe strain on their nutrition.
In mammals the corresponding limiting factors are uterine nutrition and milk
production, which together may be termed the capacity for rearing young. In the
male, however, fertility is seldom likely to be limited by sperm production but
rather by the number of inseminations or the number of females available to
him... In general, then, the fertility of an individual female will be much
more limited than the fertility of a male... This would explain why in
unisexual organisms there is nearly always a combination of an undiscriminating
eagerness in the males and a discriminating passivity in the females.
Among polygynous species, the variance in
male reproductive success is likely to be greater than the variance in female
reproductive success.
The female, with the rarest exceptions, is
less eager than the male... she is coy, and may often be seen endeavouring for
a long time to escape.
Exceptions and counter-examples of
Bateman’s principle:
Some modern evolutionary biologists believe
Bateman's principle is incorrect for such a large percentage of species that it
should no longer be considered a valid principle. Olivia Judson (2002) argues that the formulation of Bateman's
principle was limited by such things as short observation time in his
experiments. Tim Birkhead (2001) has also documented extensive examples of
exceptions to Bateman's principle, with a focus on sperm competition.
Some flaws in Bateman’s study
Researchers have recently reconstructed
Bateman’s original 1948 experiments and critiqued the results using a
present-day understanding of genetics and statistics.
They found that many of Bateman’s
conclusions were based on poor genetic techniques or statistical errors and
oversights (Snyder & Gowaty 2007)
Bateman selected his mutant strains because
they had visible morphological deformations (eyes, wings, bristles, etc.).
These mutations were easily discernible but may have interfered with mating,
mate selection, or mobility. Strains therefore had different reproductive
success.
Pure-breeding mutant strains are often
inbred, and inbred organisms typically have reduced reproductive success and
fewer viable offspring. Also, many mutant strains are bred to eliminate most
genetic variation other than the pure-breeding mutation, so individuals within
a strain are nearly clones. Samples were therefore not completely independent,
reducing the replicability and sample size of his study.
Several of the mutant strains are
homozygous lethal, and individuals heterozygous for more than one mutation may
have reduced viability. This would result in the premature death of some
offspring genotypes, biasing Bateman’s counts.
Female flies take 4 days to reach sexual
maturity, while males take only 1 day. Bateman ran experimental crosses for 3–4
days, using flies of different ages. This experiment window was not long enough
for sexually immature females to mate more than once.
Several calculations of the variance in
number of mates had arithmetic errors. New calculation shows that most of his
results were not statistically significant.
The reanalysis of Bateman’s original data
shows that reproductive success is positively and significantly correlated with
number of mates in both males and females (though the trend, as predicted, is
greater in males because they can't be pregnant). That is, both sexes benefit
from mating with multiple partners, though males can't be pregnant so they are
capable of more so.
Females can be promiscuous
Bateman’s principle implies that females
are choosy because there is little advantage for them to mate with multiple
males. However, observation of many species,
from rabbits to fruit flies, has shown that females have more
offspring if they mate with a larger number of males. This seemingly
contradicts Bateman's theory, specifically his conclusion that "while
males had more children the more partners they mated with, females did not"
(Judson 2002:). Exceptions to Bateman's principle abound, as do hypotheses
explaining the evolution of female promiscuity. Females in fact have a lot
to gain, depending on the species:
Genetic compatibility
Some combinations of male and females
genomes are incompatible, causing abortion or reduced offspring viability.
Mating with multiple males can increase likelihood of finding a compatible
partner. For example, in the pseudoscorpion Cordylochernes scorpioides,
females that mate once with two mates tend to have more offspring surviving to
adulthood than females that mate twice with one mate. This is presumably
because the female is putting her proverbial eggs in multiple baskets (Judson
2002; Knight 2002)
Reduced risk of inbreeding
Incompatibility and low offspring fitness
is common in inbred populations where genetic diversity is low. Splendid
Fairy-wrens (Malarus splendis) are relatively sedentary and have a low
dispersal rate. Though the species is socially monogamous, mating within the
social group would lead to a highly inbred population. Females sneak
copulations with males outside the group, resulting in more successful,
genetically diverse offspring (Brooker et al. 1990).
Protection against infanticide
Male chimpanzees, lions, and many other
mammals, will kill unrelated offspring in order to bring the female into
estrus, providing a mating opportunity for the male. By mating with multiple
males, a female can confuse the paternity of her offspring, and males are less
likely to commit infanticide if they may have sired the offspring (Judson
2002; Wolff & Macdonald 2004)
Bet-hedging against sterility
In some species, like the shiner perch
(Cymatogaster aggregata), copulation and fertilization are separated by several
months. If the female mated once, and the male’s sperm was unviable, she would
have to wait until the next breeding cycle to mate again. Instead, the
promiscuous female mates with multiple males to ensure that her eggs will be
successfully fertilized (Judson 2002).
Males can be
choosy:
Bateman bases his hypotheses on the
assumption that males are promiscuous because their gametes are inexpensive and
unlimited. However, the male reproductive expense can be great, and often this
results in males choosing mates carefully. Several hypotheses explain the
evolution of these behaviours.
Sperm is not always cheap
Although a single sperm normally takes
little energy to produce, sometimes it takes substantial energy to produce
them, or at least enough to fertilize a female’s eggs.
In one species of fruit fly, Drosophila bifurca, males produce sperm with
flagella 58mm long, and require 17 days for the testes to fully develop.
Several hypotheses may explain the evolution of giant sperm—the sperm act as
immediate parental investment by providing nutrition for the developing zygote;
they are large enough to block the reproductive tract of the female, preventing
sperm competition; the sperm are large enough to individually transfer to the
female, so the male only needs to deposit enough sperm to fertilize the
available eggs. Because the sperm are so big, there is a greater chance of
successful fertilization (Méry & Joly 2002).
A typical fairy-wren ejaculate may contain over 8 billion sperm (compared to
about 180 million in humans). In these species, extra-pair copulation is
common, so sperm competition is fierce. An individual can increase his chances
of fertilizing the female’s egg by producing more sperm than his competitor.
For this and many other species with a similar strategy, producing this many
sperm requires a large resource investment that may take days or weeks to
replenish (Pruett-Jones & Tuttle 2007).
Copulation can be demanding
Females of many species require multiple
copulations in order to stimulate ovulation or to produce hormones to initiate
pregnancy. This requires a high energy investment on the part of the males.
Lionesses, for example, may require the stimulation from over 100 copulations
to produce a single litter of cubs. This adaptation may ensure the strength and
fitness of the lioness’ mate, which would result in higher quality offspring
(Judson 2002).
Sex-role reversal: males may invest a lot
The most well-known exceptions to Bateman's
principle are the existence of sex-role reversed species such as pipefish
(seahorses), phalaropes and jacanas in which the males perform
the majority of the parental care, and are cryptic while the females are highly
ornamented and territorially aggressive (Emlen & Oring 1977;Knowlton
1982; Berglund, Widemo & Rosenqvist 2005). Because females in these
species display the behavior predicted for males by Bateman, many believe that
such examples actually support, rather than undermine, his principle (Flinn
2004).
Other examples of violations to Bateman's
principle
Some species in which males will guard one
female and mate only with her, attempting to prevent her from mating with any
other males. Examples include stick insects and Idaho ground
squirrels (Judson 2002:9–10). These observations also seem to challenge
Bateman's theory, specifically the assertion that "a male's reproductive
success increases with each female he mates."
Females do not always have a relatively
larger investment in producing offspring. In species that reproduce by spawning
(releasing sperm and eggs into water), for example, each sex's investment is
approximately equal. In animals with internal fertilization, many sperm must be
produced for every egg; so, even though it takes less energy to create one
sperm than one egg, males of many species spend more energy making gametes than
do females (Judson 2002:29–33).
The statement that the sex that invests the
most in producing offspring will become a limiting resource is not always true.
In flowers, for example, the female part of the flower invests more energy into
making seeds than the male part of the flower does. The reproduction of most
flowering plants, however, is limited by delivery of the male gametophyte –
pollen – not by production of the female gamete (Judson 2002:197).
Bateman's statement "there is nearly
always a combination of an undiscriminating eagerness in the males and a
discriminating passivity in the females" and his assumption that
anisogamous species would be polygynous have also been argued to be false,
because females of many species mate with several males (Judson 2002:12–13).
By [Dr.KamalenduChakrabarti]
(Dr Kamalendu Chakrabarti is an internationally
acclaimed Kolkata-based Pediatrician, a known crusader for
breastfeeding promotion in India, is an eminent writer and Health Editor at Bengal Newz.)
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