Could we healthily repopulate the world with just two people?

Question

Wouldn't severe birth defects start manifesting themselves after the first couple generations?

Answer 1

remember the bible is a fable not actual fact. no we couldnt

Answer 2

It's certainly possible. It's true it is certainly not healthy, and the possibilty of harmful homozygous mutants coming up is much higher.

However, a male and a female could, theoretically, have up to 30 children within the space of a normal human female fertility cycle (tough going on the lady though). Obviously, on average 50% of those will be female, so you have in the next generation say 15 people who can have a further 30 children each (or up to 450 children in gen 3).

As this would entail brother-sister matings (ugh) there will be a relatively high fallout of babies due to homozygous mutations (two bad copies needed for the effect of the bad gene to manifest)...

However, overall, the sheer numbers that can be generated over a period of time will exponentially increase and therefore it is certainly possible to repopulate the world (and over a prolonged period of time, natural selection would ensure the population would be healthy).

Answer 3

It would depend on the 2 people.
Inbreeding only causes defects if they are already present in heterozygous form. i.e. one good copy of a gene and one bad copy. In a normal population the bad copy would almost always be counter acted by a good copy, but in a small population bad copies may come together after 1 generation.

Theoretically if the DNA of the 2 original people was 'perfect' then there would be no serious defects. However variation would be greatly reduced (traits such as height, eye/hair/skin colour) so you might end up with a group of people who are quite alike.

I dont recommend it!

Answer 4

Genetically speaking we would need about two dozen people to repopulate safely. With a ratio of about 1:2, males to females. I remember reading somewhere that it was about 13 males and 21 females.

But it may be possible with only two people, with a miracle.

Answer 5

It's possible... but it may be difficult in many cases to see the reprecautions of inbreeding for many generations. I am a firm believer in the bible but even if you don't believe in the bible you have to believe that people at least came from somewhere and that started with just two of its.

Answer 6

We did in Kentucky. We aint that bad now are we? D@mn banjos playin in the back Cletus tell you sister/wife to shut the hell up I'm talkin on this here writing box.