Does Birth Order Determine Success?

All men may be created equal; but a look at their pay stubs will tell you that their incomes are not. Blame it on social class, education -- even luck, but according to Dalton Conley, New York University professor of sociology and public policy, inequality begins at home.Research shows that first borns (and onlys) lead the pack in terms of educational attainment, occupational prestige, income and net worth. Conversely middle children in large families tend to fare the worst.

Here's a look at what impact your birth-order may have on you:

First Borns: More conscientious, ambitious and aggressive than their younger siblings, first borns are over-represented at Harvard and Yale as well as disciplines requiring higher education such as medicine, engineering or law. Every astronaut to go into space has been either the oldest child in his or her family or the eldest boy. And throughout history -- even when large families were the norm -- more than half of all Nobel Prize winners and U.S. presidents have been birst born.

Middles: Middle children are more easy going and peer-oriented. Since they can get lost in the shuffle of their own families, they learn to build bridges to other sources of support and therefore tend to have excellent people skills. Middle children often take on the role of mediator and peacemaker.

Youngest: The youngest child tends to be the most creative and can be very charming -- even manipulative. Because they often identify with the underdog, they tend to champion egalitarian causes. (Youngest siblings were the earliest backers of the Protestant Reformation and the Enlightenment.) Successful in journalism, advertising, sales and the arts.

Only Children: Only children have similar characteristics to first borns and are frequently burdened with high parental expectations. Research shows they are more confident, articulate and likely to use their imagination than other children. They also expect a lot from others, hate criticism, can be inflexible and are likely to be perfectionists.

Twins: Because they hold equal status and are treated so similarly, twins turn out similarly in most cases.