Terry wrote:
>It may have consequences that are detectable scientifically (a la
>Glenn's concerns). If this is the case, then it is not too difficult
>to say that God's timing may be different in your three scenarios.
Glenn has more concerns. I finally found in my database some stuff I had
been looking for about embryology which has implications for the soul and
ensolation. Like that which I put out yesterday, the situations here are
similar but slightly different.
Chimeras are the result of the union of two zygotes. Given the normal
conservative view, each zygote is a human at conception. Yet, what happens
when two zygotes with two souls fuse to form one individual? Where does the
other soul go? Which soul dies? Yet with twins, where a single embryo
splits, no one has problems giving the two embryos two different souls.
With chimeras, what happens? We must pay attention to the data we see with
our eyes. And the quote below raises profound questions concerning the
possibility of making a human/chimp chimera. What would stop such a creature
from being born and living other than ethics?
"Charles Boklage believes that most malformed children who
were born as singletons actually may be the product of twin
pregnancies. This may also be true of left-handers, who are more
common among twins. He cites another interesting phenomenon,
which, although it has rarely been detected, may not be at all
uncommon. 'It is possible that I am twins. By that I mean that two
different embryos went together to make one body. We know that
occasionally happens, but it is almost never detected except in
the blood banks. I think it is actually much more common than
that. I can tell you with complete certainty that some of us are
twins who are walking around in a single body.' Such a creature is
called a chimera, after they mythological Greek monster that had
the head of a lion, the body of a goat, and the tail of a serpent.
Chimeras are easily produced in the laboratory. 'We've had
thousands of experiments with rats and mice in which we take part
of a mouse embryo and stick it in a rat embryo,' says Boklage.
'We've done it between sexes and between species. They never make
twins. They always fuse into single embryos and come out part rat,
part mouse, part male, part female, part sheep, part goat. The
forces involved in embryogenesis simply overpower the differences
in their origins. I'm sure there are creatures too far apart to
put together, like a mouse and a chicken. But when these events
occur in human development, it simply goes on.' Chimeras sometimes
happen in nature when littermates fuse together. The fact that
this happens in humans was only discovered when donors in blood
banks were found to be carrying two different blood types; it
could mean that fraternal twins merged in the womb. Most human
chimeras are to some extent hermaphrodites, with ambiguous
genitalia. Of course, there is no way to discover if identical
twins have merged, since their genes and blood types are the same.
In these cases, the twins don't vanish, they amalgamate." [GRM: does the
zygotic soul split and then fuse again as well?]
"When an infant twin girl, year and a half old, recently
appeared in the Department of Paediatrics at the British Columbia
Children's Hospital in Vancouver suffering from chronic lung
infections, Judith Hall routinely checked for cystic fibrosis. By
analyzing the chloride level in her sweat, Dr Hall got a positive
diagnosis. 'We then decided it was time to check the twin,' says
Hall. As it happens, when these twins were born their obstetrician
carefully examined the membranes of the placenta to determine
their zygosity. There was a single chorionic sac, so the doctor
assumed that the girls must be identical. And yet, when Hall
tested the eighteen-month-old twin for cystic fibrosis, there was
no sigh of the disease. 'We then decided to do blood studies,
looking for common mutations that occur in cystic fibrosis˜and
they weren't there in either twin! So we scratched our heads. We
then decided to take a bit of skin, and when we did that, the kid
with cystic fibrosis had the common mutations and the other
didn't.' This was a terrific muddle. The other twin was not even a
carrier of cystic fibrosis; no evidence of the gene at all. DNA
tests showed that the girls were not, in fact, MZ twins.
Apparently they were the result of two separate acts of
conception, but the zygotes implanted so close to each other in
the uterus that the placentas fused. Further testing showed that
the diseased twin was carrying the blood of the healthy twin. They
had evidently shared the same circulation in the womb, which is
common among identicals, but rare among fraternals. 'They were two
separate creatures, but they shared their blood in the placenta at
such an early age that one twin actually took over for the
abnormal twin, so its blood was healthy but the rest of its body
had cystic fibrosis,' says Hall.' That's a chimera.' "Lawrence
Wright, Twins, (London: Phoenix Books, 1997), p. 82-84
Where is the soul?
"If most of the cells of the blastocyst give rise to the
trophoblast, exactly how many cells actually form the embryo? ONe
way to answer this question is to produce ALLOPHENIC MICE.
Allophenic mice are the result of two early-cleavage (usually 4- or
8-cell) embryos that have been aggregated together to form a
composite embryo. As shown in Figure 28, the zonae pellucidae of two
genetically different embryos are removed and the embryos brought
together to form a common blastocyst. These prepared blastocysts are
implanted into the uterus of the foster mother. When they are born,
the allophenic offspring have some cells from each embryo. This is
readily seen when the aggregated blastomeres come from mouse strains
that differe in their coat colors."~Scott F. Gilbert, Developmental
Biology (Sunderland: Sinauer Assoc. Inc., 1991), p. 95
where is the soul
The experimental data of Mintz (1970) are that 73 percent of the
double embryos yield allophenic mice, thus suggesting that three
blastomeres of the blastocyst produce the entire embryo. Markert and
Petters (1978) have hown that three early 8-cell embryos can unite to
form a common compacted morula and that the resulting mouse can hav
the coat colors of the three different strains. Therefore, while i
is not certain that three is the absolute number of blastomeres tha
form the embryo, we can be fairly certain that the number is not
much greater and that most of the cells of the blastocyst never
contribute to the adult organism."~Scott F. Gilbert, Developmental
Biology (Sunderland: Sinauer Assoc. Inc., 1991), p. 95-96
glenn
see http://www.glenn.morton.btinternet.co.uk/dmd.htm
for lots of creation/evolution information
anthropology/geology/paleontology/theology\
personal stories of struggle
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