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pivoxa15
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If two human siblings were born within 365 days of each other then they must be twins (i.e. born on the same date)?
Please explain.
Please explain.
J77 said:However, more sprogs are easily conceived after the first one pops out, after 9 months.
Yes - but it it not common. The first child could be born in Jan, and then the second conceived in late March or early April and then born in Dec. Obvoiusly, as Jim indicated, the first child would be conceived during the previous year. It is not possible to conceive, deliver and then conceive and deliver, in the same year, and not have premature children.pivoxa15 said:Is it possible for two sibilings to be born within the same year but are not twins? So one baby at a time in mother's womb but born within the same year although none born prematurely.
Astronuc said:Yes - but it it not common. The first child could be born in Jan, and then the second conceived in late March or early April and then born in Dec. Obvoiusly, as Jim indicated, the first child would be conceived during the previous year. It is not possible to conceive, deliver and then conceive and deliver, in the same year, and not have premature children.
Usually however, a woman who breastfeeds delays subsequent ovulation, while breastfeeding.
I have one brother 14 months younger than me, so my parents go busy soon after I was born.
pivoxa15 said:What do you mean by conceived? The important thing is that the siblings are born (out of mother's stomach) in the same year but none born prematurely.
Moonbear said:Conception refers to fertilization...the time when intercourse actually occurred that the pregnancy was initiated. And, just for accuracy, since this is a science forum, embryos/fetuses develop within the uterus, not the stomach. If you wish to refer more generally to the area of the body rather than to internal organs, abdomen is an acceptable term.
So, yes, if you are referring to birth only, and not the entire pregnancy, then it is possible for two siblings to be born within the same year, although very uncommon for the reasons already discussed above.
DaveC426913 said:Ah.
Well, just because they're born at the same time doesn't mean they're identical twins. Certainly in this day and age of superovulation technology, it is quite possible that they are due to the simultaneous fertilization of two different ova (as opposed to the splitting of a single ovum after fertilization). That would make them no more twins than any other pair of siblings.
BTW, it is also possible (and has happened) that "twins" do not even share the same father.
pivoxa15 said:Twins without the same father? That must be freaky as in low probability.
The sibilings I had in mind look alike enough to be sisters but not any kind of twin.
pivoxa15 said:I raised the question because I know two sibilings in the same year level which dosen't look alike enough to be twins.
So that is a chance that they were born at different times of the year.
pivoxa15 said:The sibilings I had in mind look alike enough to be sisters but not any kind of twin.
brewnog said:Someone correct me if I'm wrong, but non-identical twins don't typically look any more alike than any other siblings. An ex girlfriend of mine looked little like her (non-identical) twin sister, and my current girlfriend's twin is a boy...
I'm sure I heard a news story on something like this just last week...Danger said:It's been so long (+/- 40 years) that I honestly can't remember whether I met them or only read about them, but there were a couple of girls who were born as twins with 2 different fathers. I don't know whether it was the result of a three-way or just a couple of different partners very close together chronologically. Unfortunately, my sex education is of the back-alley variety, so I'm not too sure about the medical aspects of that situation.
fleem said:Hope this wasn't already pointed out, but on a side note apparently it is possible for two babies to grow in the womb together that were fertilized from ovulations a month apart. Its called Superfetation.
pivoxa15 said:Someone mentioned that non identical twins look as differently to each other as siblings born some time apart. I don't believe it!
WHy are some twins identical and some not? THis question may shed light to the above.
Moonbear said:Note that even identical twins often look a bit different, especially as they get older. That's because some of our appearance is not due to purely genetic factors, but some environmental factors, i.e., how much weight we gain, sun exposure (I have cousins who are identical twins and look very little alike as adults...one loved going out in the sun as a teen, and the other pretty much stayed indoors, so one has a lot of sun damage, wrinkles, freckles, and the other doesn't), and even hairstyle can make you look pretty different.
fleem said:The eggs that the mother produces have different combinations of genes from the mother--each egg has a different set of genes. Likewise The sperms that the father produces have different combinations of genes from the father. So when one egg and one sperm unite, they make a unique individual that is NOT an exact copy of either the mother or father.
Usually just one egg is released from an ovary. After it is fertilized by a sperm it begins to divide into more and more cells and grows into a baby.
Sometimes, though, more than one egg is released and each gets fertilized by a different sperm. These grow into twins which are not identical. Since each baby grew from a separate egg+sperm combination, they are no more similar than their other brothers or sisters born years earlier or later.
fleem said:However, sometimes AFTER a single egg+sperm are combined, when the cells start to divide to make a baby, some of those early cells don't stick together well and break away. Now you have two or more clumps of cells that came from the SAME egg+sperm! So the babies that grow from each clump are identical.
pivoxa15 said:Still, eggs produced within a period of time can be different to eggs produced at a later time. Same as sperms. So non identical twins can still be more similar than to siblings born years apart? Say 10 years would be a noticable difference.
This raises the question: Is it true that the sperm and egg 'quality' decline as one ages? Although someone define quality as I don't know how to. If so when is the peak times for male's sperm and female's egg?
That would be much more rare? How rarer compared to non identical twins?
pivoxa15 said:Birth defects being the genes not properly transcribed and carried out?
When that happens at a minor level, the effects will show later in the baby's life?
What do you mean by degrade of sperm and egg?
fraternal twins being twins with different fathers?
Moonbear said:It takes some time for ovulations to resume after one gives birth, though that time varies among individuals and whether or not one is breast feeding. But, still possible to have a baby born in January and another in December (especially if the second is a bit premature).
pivoxa15 said:Still, eggs produced within a period of time can be different to eggs produced at a later time. Same as sperms.
No, twins do not always share the same birthday. While they are typically born on the same day, it is possible for them to be born on different dates depending on the timing of the labor and delivery.
It is estimated that about 80% of twins are born on the same date. This is due to the fact that most twins are conceived at the same time and have the same gestational period.
Yes, twins can be born on different days. This can happen if the labor and delivery process is prolonged and one twin is born after midnight, or if there is a significant time difference between the births.
Yes, it is common for twins to be born at different times. This can happen due to various factors such as the position of the twins in the womb, the length of the labor, and any complications during delivery.
There is no scientific evidence to suggest that the birth order of twins has any impact on their personalities. While some people may believe that the firstborn twin is more dominant, this is not necessarily true and each twin's personality is unique and influenced by a variety of factors.