Biological Features Necessary for a Humanoid to Have a Much Higher Rate of Reproduction?

Question

So for this question there’s a Mad Scientist/Dark Lord that wants to engineer a race that can out breed mankind and carry him to victory. He has access to sufficiently advanced genetic engineering/plot contrivances to get the job done, but what anatomical features does he actually have to give to his genetically engineered humans to have them reproduce faster? Is it wider hips and narrower heads? Precociousness? A modified metabolism?

Requirements:

•They have to be intelligent enough to do basic tasks and take orders, intelligence may be significantly inferior to the average human but they still have to be capable of wielding weapons, harvesting crops and smashing rocks.

•They must have a fertility rate that significantly outpaces that of humans, it can’t be an insignificant difference.

•They can’t be absurdly smaller than normal humans.

Note: If it’s too tricky to modify humans to be faster reproducers, what would some other genetic engineering options be?

Answer 1

Mass production of eggs would be the easiest, but staying as realistic as possible, I would provide the following:

The biggest drawback of humans vs most other creatures is our growth rate. There are unconfirmed theories that shows that while growing up, our brains consumes most of the energy our bodies receive, and leaves the body behind. Given this factor, if glucose can be administered biologically through the mother of children to assist in both growth rate of the brain and body we would be able to improve our overall growth rate.

There is a rare condition called macrosomia. This is caused by genetic disorders such as obesity and diabetes. Macrosomia causes babies in the womb too grow at a faster rate and at normal pregnancy times are a lot larger than normal babies. If a mother can be genetically modified to boost this condition along with the high concentration of glucose, it could be possible to have babies born as early as 3 months at the normal size of a 9 month birth.

Twin births are caused when 2 eggs are present in the womb. Given the above factors as well as twin births it would result in a single mother should be capable of producing 6 babies in 9 months and possibly more if the eggs are increased in the womb to create triplets.

At a steady increased growth rate, Children can possibly reach full adulthood at 5 to 6 years of age, a lot sooner if the rate is massive.

There are however other factors to consider. One being overpopulation. Salmon produces hundreds of thousands eggs. If these fish had the lifetime of a human being, it would mean that the population would increase so fast that they would fill the oceans. Food would no longer be readily available and there would be a mass extinction. Instead, they have a life cycle of 3 to 8 years where after spawning, the parents would die. given the rate at which human population would reproduce, the life cycle should be dramatically reduced in order to ensure huge over population does not occur. We would expect a life cycle of a maximum of 20 years, perhaps even less.

Food production would need to increase, this would mean that plant proteins would be the most common as it can be grown quicker than most meat producing animals.

Last, but not least, gender factors of human babies born would need to have a steady ratio. If too little females are born, there would be a very high possibility of in breeding as there are not enough females to go around. If there is too many females, the growth rate of the army would be inefficient.

Given the above ratios of human baby births as twins as well as the fact that all children would be able to produce more children at the age of roughly 6 years old. a single mother should be able to produce around 112 babies in her lifetime. a million mothers would be able to then produce around 112 Million babies in 14 years.

There are rare cases of a mother producing octuplets which if developed instead of twins, could increase this number dramatically.

Answer 2

There are several options:

1) Larger brood size: Humans typically only give birth to a single child at a time. Simply ensuring twins most of the time will double reproduction. Larger broods will require breast-feeding in turns unless the women are equipped with more mammary glands.

2) Shorter gestation and interpregnancy periods: The time between pregnancies is a major factor. Human women are pregnant for 9 months, and becoming pregnant again less than 12 months after giving birth is associated with birth complications, making time between births at least 19 months. If this could be reduced to, say, 12 months, this alone will increase births by a third.

3) Younger age of fertility: How young women can be mothers is a huge factor. Human girls as young as 6 years old have been known to give birth, but it is rare for women younger than their mid teens to become mothers. Halving the average age of fertility could halve generational length and produce far more offspring in the longer term.

4) Gender imbalance: If (say) three out of four children are females, half again as many people will be able to give birth. Gender imbalance can at most double the share of women, compared to normal humans, and if males make stronger warriors or workers, you would not want too great a female to male ratio.

Let us assume that force-breeding normal humans would mean brood sizes of 1, 18 months between pregnancies, and 8 children (half of each gender) on average between age 15 and age 27 (average 21 years for a generation), then the female population will quadruple in 21 years on average, and with that, the birth potential.

Let us now assume average brood size of 2, 9 months between pregnancies, and 12x2 children (18 female, 6 male) between ages 8 and 20 (average 14 years for a generation), the female population will increase 18-fold in 14 years and 76-fold in 21 years. That is quite a difference!

Answer 3

Simply said eggs. If we look at how many eggs most animals are able to put out it will dwarf the amount of live births(highest mammals do it around 30, while fish and insects can go in to the millions). And if you got full genetic control you could have the breeding mother be able to get pregnant straight after the first batch of eggs.

After that it's a matter of making them hatch. A humanoid with eggs would have (initially) smaller offspring then regular humans (otherwise poor women if they have to put out several baby sized eggs). This means that these new egg people will need more time to grow to full maturity and seeing there will be a lot of them you will need a lot of babysitters.

So this way your army will be larger faster but it will also take them slightly longer to get battle ready.

Answer 4

Option 1: The most important aspect of why human births take so long are not fertility, but length of pregnancy. If you make the cells of the unborn child multiply faster, your babies will grow much quicker and be able to be birthed. Add to that better given instincts, like that of newborn cows or foxes, and you'll sooner have "useful" babies that aren't entirely dependent on outside help for the first 2-4 years of their life.

Option 2: If you want to make your dark lord even more dangerous and the world more disturbing, you can have his humans only be born as heads and maybe torsos, and then have body-parts that have been artificially created (or taken from corpses or live victims, etc.) operated onto these human frames. That also reduces the time needed for birth, as you save on unnecessary limbs.