How long would the Village of Motunui have lasted Re inbreeding

[SleepingStandingUp]

Been a few generations since anyone crossed the reef right, and I expect its a fairly closed population anyway.

So if Mo hadn't gone and saved every one and got them back out on the water, do you think eventually the inbreeding would have done for the population? Or is there enough passing sailors to mix it up?

But they were "voyagers" originally, so likely most of them were unrelated for a few generations anyway.
It's all that staring at the water I'd be worried about and only using coconuts for EVERYTHING - hardly a balanced diet!

true of any of the isolated islands in real life surely?

There must have been generations between passing sailors.

But Steppe I don't spend every day with them so their fortune is less of an issue. But yes.

I also what will become of her Re marriage and kids. Can't imagine Dad is progressive enough to not care if she doesn't carry on the lineage but there doesn't seem many contenders. I hope they find another island and she gets to choose her partner for love.

But now you have said it, I am fascinated, why didn't all these remote communities suffer from massive in breeding.

Sorry, not the spirit of the thread, but you have sent me off down an internet rabbit hole....

Well they probably don't have access to contraception so each family has loads of children, then they all get together and have loads and it goes on that way.

Plus first cousins isn't supposed to be an issue.

There was regular travel between many of the Pacific islands... The sea was seen as something that linked them, not something that separated them.

And in certain communities there is huge inbreeding and certain congenial issues are more prominent. I guess those family lines would die out of they weren't producing children who would go on to procreate.
And when Dad doesn't ban you from crossing the reef, you can go off to another island and find yourself a hot guy who isn't related to you!

There would have been many first cousin marriages probably, as siblings wouldn't have been allowed but cousins probably OK in many communities (not talking specifically motonui or Polynesia here hahaha just everywhere)
I think the likelihood of things going wrong wrt genetic defects etc would have definitely been increased but with poor medical care etc babies would have not thrived and sadly passed or not lasted long after birth when things went wrong, sorry to be depressing but probably true. That way the 'strong' genes probably got passed on as they made it to breeding age successfully?

Didn’t the Pitcairn Islanders have inbreeding issues alongside the horrendous child abuse scandal?

Not sure I remember that tbh but like Jean said u guys anything serious would kill the line. Off to Google....

Didn’t the Pitcairn Islanders have inbreeding issues

The original settlers of Pitcairn were the Bounty mutineers and their Tahitian wives, along with 6 Tahitian men, so there would have been some relative diversity early on, although the breeding became closer as the years went on. All of the Pitcairn Islanders moved permanently to Norfolk Island in 1856 (although 46 later returned to Pitcairn, which are the descendants of the current residents).

There have only been two children born on Pitcairn in last 25 years, and there are restrictions on bringing anyone under the age of 16 onto the island. There have only been two new permanent residents ever allowed to settle there, a retired couple. At this time there are only 50 residents on the island, most past childbearing age, and it is likely the population will die out in coming years, as a lot of the younger residents tended to move away to Australia or New Zealand and chose not to return.

About half of Norfolk Islanders (the island has about 1800 residents) can trace their history back to the original Pitcairn Islanders, with the rest being from immigration onto Norfolk. Until recently, most Norfolk students moved to Australia for their senior high schooling, and anyone wanting to complete tertiary study still does so, where they often meet people to marry and have children with.

@steppemum
I lived in a remote Aboriginal community in Australia. Aboriginal people have a ‘skin name’. Your skin name depends on the skin name of your parents so for example my skin name is Nungarrayi which means my ‘straight skin’ (the skin name of the man I would have to have children with to prevent inbreeding) is Jangala (female skin names start with N, males J). Our children are Nampijinpa/Jampijinpa. It’s an ancient system which wasn’t deviated from historically. Nowadays it is and there’s a derogatory term for that as it’s still not really the done thing.

It goes around like that in a circle, 16 skin names in total - 8 female, 8 male.

Zoroastrianism has huge problems with inbreeding, as they're not allowed to marry out.

I've always thought that Motanui is based on the Anutan tribe that live on the island of Anuta in Polynesia. The island is only half a mile across and had a population of about 300... There was a Bruce Parry documentary on it. The people certainly didn't look inbred, but even there on such a remote island (3 days sailing from nearest mainland) a lot of the people were educated on the mainland and then returned to the island later in life because they preferred island life to working in a job in a city. I guess there was plenty of scope for coming across fresh blood that way...

Anyway I bloody love the movie and I'd recommend the documentary to anyone else that likes the movie too. It looks like paradise.

I want them to make a sequel!!

But whereas it's normally a none royal girl getting rescued and married it'd be the reverse.

Ooh live action with Aquaman as her Daddy. I'd be her step Mom if her mum wanted to go to New Zealand ')

That’s really interesting Midnite and Ahoy.

@AhoyDelBoy
Thank you that is really interesting.
I spent far too long last night googling this!

Basically, a summary of google says

1. very few (if any) communities are genuinely isolated, there is contact between islands etc, as pp said, island communities tend to see the ocean as linking them, and travel by boat.
2. Very old non island communities tend to have strict taboos (like Ahoy's skin name) and/or have systems for meeting up with, and exchanging brides with, other communities
3. Inbreeding is not as easy/common as you think, in that a severe genetic mutation will lead to death and so doesn't continue, and a mild one will build up in the community, but not as fast or as often as we might think (basically you need hundreds of years for real problems). One of the island groups (not Pitcairn I think) has a high incidence of colour blindness due to in breeding, but this isn't a major issue.
4. The bigger problem with lack of genetic diversity is that all the members of a population have the same weaknesses, so if a new illness appears, they are all likely to either survive or all die, whereas in a diverse population, some survive and some die.

Fascinating stuff

I love that this is a serious Science thread based on Moana 😂

I think that often with remote communities, such as Pitcairn, when students need to leave the island to complete their studies, they often don't return (or only return in their later years when their own children have grown and moved out) as there is just not enough of a drawcard to living on a remote island for many young people, although they often like to return to that community when there is no longer the pressure to earn and raise children within that community. Somewhere like Norfolk Island is more sustainable than Pitcairn, as students can complete year 12 on the island so don't tend to need to move away (unless they want to access tertiary education), and they are able to access Australia via a relatively short flight (Pitcairn is only accessible by boat). I think that can makes sustaining a population more viable.

Yeah I fantasise about living on an island accessible by boat (a warm one though, not a Scottish one!!) but accessible by plane is too far for more than a fortnight's holiday

Effects of inbreeding on Pingelap, a small coral atoll.

The fisherman is an awesome example of survival and adaptation passing on genes. If he gets all the best fish and all the best women and makes all the healthiest babies because he catches all the best fish he could raise a whole generation of light night seers and so on and so forth