A new UK research has found that rich men sire more children than their not so well-off counterparts.
The new study involved thousands of middle-aged British men.
Daniel Nettle, a behavioural scientist at Newcastle University, UK, who led the new study, said that women are more likely to marry men who can provide for them and their children than penniless men.
According to Rosemary Hopcroft, a sociologist at the University of North Carolina in Charlotte, who is not a part of the study, said that census surveys have suggested that wealthier men have fewer kids.
However, surveys are tricky as they involve household income and tally only a mother's children. The children of divorced and remarried men tend to get left out, she said.
To correct for the bias, Nettle and Newcastle colleague Thomas Pollet looked at previously gathered data on more than 11,000 British men and women, all born between 3 and 9 March 1958, called the National Child Development Study.
The study has tracked income, marriage and fertility of study participants since birth. "It's a great resource," Nettle says.
Now that volunteers have entered their late 40s - the study used data from 2004 - nearly all participants have stopped having children.
With carefully collected figures on male and female income and fertility, Nettle and Pollet found that, for men, the more money they make, the more kids they sire on average.
They found that men who earn 10,000 pounds a year fathered one child on average, while fathers who pulled in 50,000pounds-plus sired more than two kids.
But rich men didn't have larger families, rather they are more likely to find mates, Nettle says.
The study has been published in The American Naturalist.