We'd go extinct. Spiders can have hundreds of offspring per 'birth.' Humans have, on average, about one. You need each woman to have at least 2 children for pop

We'd go extinct. Spiders can have hundreds of offspring per 'birth.' Humans have, on average, about one. You need each woman to have at least 2 children for populations to stay the same. Which, in this case would mean you'd need at least 2 men. An evolution (or artificial 'population management') where males are 66% likely or otherwise born at a 2:1 ratio wouldn't work because then you need each woman to have 3 children to create a sustainable population, meaning you need an even higher ratio of males - and so on recursively towards infinite male:female ratios.