Story about astronauts who landed on an alien planet. The aliens would corral all the female aliens in a pen. The males would take on a new alien wife every month (year?) and kill the old wife. The astronauts decide to help the females. The females rebel and kill the astronauts saying they threatened their way of life. Who wrote it? Title? Read as a child....think it was a short story in a book with many other stories.
'Shall we go down and have a closer look?’ Hum asked.
‘All right. I think we have time — wait! What day is this?’
Hum calculated silently, then said, ‘The fifth day of Luggat.’
'Damn,’ Cordovir said. ‘I have to go home and kill my wife.’
'It’s a few hours before sunset,’ Hum said. ‘I think you have time to do both.’