Trying to find an old book with sentient marsupial aliens.
It was an old paperback, likely written in the seventies. I don’t remember the title or the author.
There were multiple alien races. There were humans in the story, but I don’t think it took place on earth. I have a vague idea that there was some diplomatic stuff going on.
The marsupial thing was interesting because birth control wasn’t an issue for them. Marsupials give birth when their babies are about the size of jellybeans. The newborn then has to find its way to the pouch, an epic journey, truly survival of the fittest. The marsupial aliens in the story weren’t emotionally invested in these fetuses (feti?), viewing them the same way humans would menstrual discharge. They felt sorry for the females of placental races because of the terrible burden that kind of reproduction puts on them.
I don’t remember any of the characters. I don’t remember the story. But that one bit of world building absolutely fascinated me. If anyone has read it or knows of it, I would be really grateful to know the name because I’d like to revisit it.