Before we start we have to understand Gotra
System is different from Cast System. In Veda’s there is no any mention of Cast
System, though Social Strata based on kind of work is there. We would discuss
cast sytem some other time and its origins.In Hindu society, the term gotra
means clan. It broadly refers to people who are descendants in an unbroken male
line from a common male ancestor. However, all families having same gotra need
not be cousinsThey can be descendants of sons or disciples or even adopted sons
of the Rishi(Seer), who is the root and whose name is used as Gotra. For
example if a person says that he belongs to the Kutsa Gotra then it means that
he traces back his male ancestry to the ancient Rishi (Saint or Seer)
KutsaGotra means cowshed (Go=Cow, tra=shed) in Sanskrit. Pāṇini defines gotra
for grammatical purposes as apatyam pautraprabhrti gotram ,which means the word
gotra denotes the progeny (of a sage) beginning with the son’s son.This system
was started among Brahmins, with a purpose to classify and identify the
families in the community. Later term gotra,
itself, according to strict Hindu tradition is used only for the lineages of
Brahmin, Kshatriya and Vysya families. Hindu Brahmins identify their male
lineage by considering themselves to be the descendants of the 8 great Rishis
i.e Saptarishis (The Seven Sacred Saints) + Bharadwaja Rishi. So the list of
root Brahmin Gotras is as follows :
1.
Angirasa
2.
Atri
3.
Gautam
4.
Kashyapa
5.
Bhrigu
6.
Vasistha
7.
Kutsa
8.
Bharadwaja
The offspring (apatya) of these eight are gotras
and others than these are called gotrâvayava.These eight sages are called
gotrakarins from whom all the 49 gotras (especially of the Brahmins) have
evolved. For instance, from Atri sprang the Atreya and Gavisthiras gotrasIn
almost all Hindu families, marriage within the same gotra is prohibited, since
people with same gotra are considered to be siblingsBut the hidden reason
behind this practice is the Y Chromosome which is expected to be common among
all male in same gotra. So, the woman too carries similar X Chromosome and if
married, their offspring may be born with birth defects.Few families even
maintain their Pravara. Pravara is a
list of most excellent Rishis/Persons in a Gotra lineage. As we saw earlier,
some of the descendants of the most ancient Gotras started their own Gotras,
however they maintained a list of Pravaras while doing so and attached the list
of their most excellent Ancestors with this derived Gotras.
For instance the Vatsa Gotra has Bhargava,
Chyavana, Jamadagnya , Apnavana as their Pravaras. What this means is that
Vatsa Gotra has in its lineage all these Gotras and traces back its root to
Bhrigu Rishi in the list of Gotrakarins. It connects to the root Seer.
Gotra is always passed on from father to
children among most Hindus, just like lastname(surname) is passed on worldwide.
However, among Malayalis and Tulu’s its passed on from mother to children
.Additional rule in the Gotra system is that, even if the Bride and Bridegroom
belong to different Gotras, they still cannot get married even if just one of
their Gotra Pravara matches. Now, why only male carries fixed lastname and
gotra and why female can change her lastname, gotra after marriage ?
Genes & Chromosomes among Humans
Humans have 23 pairs of Chromosomes and in each
pair one Chromosome comes from the father and the other comes from the mother.
So in all we have 46 Chromosomes in every cell, of which 23 come from the
mother and 23 from the father. Of these 23 pairs, there is one pair called the
Sex Chromosomes which decide the gender of the person. During conception, if
the resultant cell has XX sex chromosomes then the child will be a girl and if
it is XY then the child will be a boy. X chromosome decides the female attributes
of a person and Y Chromosome decides the male attributes of a person. When the
initial embryonic cell has XY chromosome, the female attributes get suppressed
by the genes in the Y Chromosome and the embryo develops into a male child.
Since only men have Y Chromosomes, son always gets his Y Chromosome from his
father and the X Chromosome from his mother. On the other hand daughters always
get their X Chromosomes, one each from both father and mother. So the Y
Chromosome is always preserved throughout a male lineage (Father – Son –
Grandson etc) because a Son always gets it from his father, while the X
Chromosome is not preserved in the female lineage (Mother, Daughter, Grand
Daughter etc) because it comes from both father and mother.A mother will pass either
her mother’s X Chromosome to her Children or her father’s X Chromosome to her
children or a combination of both because of both her X Chromosomes getting
mixed (called as Crossover). On the other hand, a Son always gets his father’s
Y Chromosome and that too almost intact without any changes because there is no
corresponding another Y chromosome in his cells to do any mixing as his
combination is XY, while that of females is XX which hence allows for mixing as
both are X Chromosomes. Women never get this Y Chromosome in their body. And
hence Y Chromosome plays a crucial role in modern genetics in identifying the
Genealogy ie male ancestry of a person. And the Gotra system was designed to
track down the root Y Chromosome of a person quite easily. If a person belongs
to Angirasa Gotra then it means that his Y Chromosome came all the way down
over thousands of years of timespan from the Rishi Angirasa!. And if a person
belongs to a Gotra (say Bharadwaja) with Pravaras (Angirasa, Bhaarhaspatya,
Bharadwaja), then it means that the person’s Y Chromosome came all the way down
from Angirasa to Bhaarhaspatya to Bharadwaja to the person. This also makes it
clear why females are said to belong to the Gotra of their husbands after
marriage. That is because women do not carry Y Chromosome, and their Sons will
carry the Y Chromosome of the Father and hence the Gotra of a woman is said to
be that of her husband after marriage.
Shrinking size of Y Chromosome
Y is the only Chromosome which does not have a
similar pair in the human body. The pair of the Y Chromosome in humans is X
Chromosome which is significantly different from Y Chromosome. Even the size of
the Y Chromosome is just about one third the size of the X Chromosome. In other
words throughout evolution the size of the Y Chromosome has been decreasing and
it has lost most of its genes and has been reduced to its current size.
Scientists are debating whether Y Chromosome will be able to survive for more
than a few million years into the future or whether it will gradually vanish,
and if it does so whether it will cause males to become extinct! Obviously
because Y Chromosome is the one which makes a person male or a man. Y
Chromosome has to depend on itself to repair any of its injuries and for that
it has created duplicate copies of its genes within itself. However this does
not stop DNA damages in Y Chromosome which escape its local repair process from
being propagated into the offspring males. This causes Y Chromosomes to
accumulate more and more defects over a prolonged period of evolution and
scientists believe that this is what is causing the Y Chromosome to keep losing
its weight continuously. Y Chromosome which is crucial for the creation and
evolution of males has a fundamental weakness which is denying it participation
in the normal process of evolution via Chromosomal mix and match to create
better versions in every successive generation, and this weakness MAY lead to
the extinction of Y Chromosome altogether over the next few million years, and
if that happens scientists are not sure whether that would cause males to
become extinct or not. And that is because Scientists are not sure whether any
other Chromosome in the 23 pairs will be able to take over the role of the Y
Chromosome or not. On the other hand, it is not necessary that humanity will
not be able to survive if males become extinct. Note that females do not need
the Y Chromosome, and since all females have X Chromosomes, it would be still
possible to create a mechanism where X Chromosomes from different females are
used to create offspring, say like injecting the nuclei from the egg of one
female into the egg of another female to fertilize it and that would grow into
a girl child. So yes, that would be a humanity where only females exist.
Gotra System helps to protect the Y
Chromosome from becoming extinct
Even modern scientists have concluded that
children born to parents having blood relation (like cousins) can have birth
defects. For example, there is a recessive dangerous gene in one person. What this
means is that say a person is carrying a dangerous abnormality causing gene in
one of his chromosome, but whose effect has been hidden in that person (or is
not being expressed) because the corresponding gene in the pairing Chromosome
is stronger and hence is preventing this abnormality causing gene from
activating. Now there are fair chances that his offsprings will be carriers of
these genes throughout successive generations. As long as they keep marrying
outside his genetic imprint, there is a fair chance that the defective gene
will remain inactive since others outside this person’s lineage most probably
do not have that defective gene. Now if after 5-10 generations down the line
say one of his descendants marries some other descendant who may be really far
away cousins. But then there is a possibility that both of them are still
carrying the defective gene, and in that case their children will definitely
have the defective gene express itself and cause the genetic abnormality in
them as both the Chromosomes in the pair have the defective genes. Hence, the
marriages between cousins always have a chance of causing an otherwise
recessive, defective genes to express themselves resulting in children with
genetic abnormalities. So, Ancient Vedic Rishis created the Gotra system where
they barred marriage between a boy and a girl belonging to the same Gotra no
matter how deep the lineage tree was, in a bid to prevent inbreeding and
completely eliminate all recessive defective genes from the human DNA.
