That's how I understood it as well, but it seems to conflict with the researchers not being able to pick between hypotheses. If one hypothesis has the female gr

That's how I understood it as well, but it seems to conflict with the researchers not being able to pick between hypotheses. If one hypothesis has the female growing their arsenal of antidotes, that is incompatible with the result that past males caused more deaths in future females. Since they didn't reject either hypothesis, neither can have been that.