WASHINGTON (WASHINGTON POST) - Only about 200 women from all of San Francisco get to be members of a philanthropic group that dates to 1929. To qualify, you have to be college-educated professionals; young (21 to 35 years old); and have a track record of commitment to your community and your profession.

Oh, and one other thing: You have to be single and never-married. If you're a member and you get married, you get kicked out.

What do these young, accomplished and generous single women call themselves? The Spinsters of San Francisco, a nonprofit with a prestigious pedigree. At first, it was a social club, but since 1957 philanthropy has become increasingly important. Each year, the group chooses a local charity and hosts three formal fundraising events and other informal volunteer activities.

With their charitable acts, the Spinsters are shattering one of the most stubborn stereotypes of people who are single - that they are selfish. Turns out, they are not just some quirky group. Research shows that today's single women have a more impressive role as budding philanthropists than anyone realized.

In every relevant study my colleagues and I have done, we found evidence that singles are stereotyped as selfish. When we asked participants to tell us what comes to mind when they think about married people, nearly every other person (49 per cent) mentioned characteristics such as giving, caring or kind. When participants instead thought about single people, hardly anyone (2 per cent) described those qualities.

When we created biographical sketches of single and married people that were identical in every way except for their marital status, college students as well as community members rated the single people as more selfish than the married people.

And, in a finding that broke my heart (if not my hypothesis), single people rated other single people as more selfish, too.

A pile of studies stands in defiance of the stereotype of the selfish single person. Single people are more likely than married people to help friends, neighbors and co-workers with rides, errands, shopping, housework and yard work. They're also more likely to offer advice and support. When aging parents need help, they are more likely to get it from their grown children who are single than from those who are married. When other people need help for three months or more because of illness or disability, again it is single people who are more likely to provide it.

Single people volunteer more than married people for organizations benefiting the arts and culture, sports groups, health organizations, environmental groups, animal-care organizations, public safety groups, even educational and youth services. Only one category gets more help from married people: religious organizations. That difference, though, is bigger than any of the differences favoring single people.

The finding of greater giving to religious organisations by married people is part of the standard story of marriage, religion and philanthropy. Religious people are more giving than nonreligious people, and married people are more religious than single people.

Now that people are staying single longer than ever before, and the emerging generation is less religious than their elders, philanthropic organisations are concerned.

Should they be?

Answers come from analyses of single adults' patterns of giving to charitable organisations. Among those who are under 45 and unaffiliated with a religion, single women gave about twice as much as single men.

Surprisingly, those single women gave about double the amount to charitable organisations as the single women who were religious but infrequently attended services. And among the religiously unaffiliated, in a twist that challenges the image of philanthropists as old people but that would make the Spinsters proud, the younger single women gave about two-and-a-half times as much as the older ones.

A comparison of the charitable donations of today's 25- to 47-year-olds to the same age group 40 years ago showed that contemporary couples are giving less. So are single men. Single women, though, are holding their own. They are giving just as much as their foremothers.

Why do single women give more than single men? Helen Dunbar, a 53-year-old single woman living near Manchester, England, believes that "women, single or not, are deeply affected by societal expectations that we be more giving, caring and nurturing than men."

Jo Cox-Brown, a 41-year-old single woman entrepreneur from Nottingham, England, thinks that women generally "are more aware of need than men."

Research shows that women are in fact more giving, more empathetic and more nonverbally sensitive than men, though studies rarely examine these inclinations through the lens of marital status.

Single people have too often been invisible to universities and other nonprofit organisations that target their "typical donor profile - heterosexual couple, with the husband making most of the financial decisions." When they organise events in ways that are unfriendly to single people and when their marketing materials feature couples and two-parent families, it is as if they are saying to singles: "We are interested in donations, but not from you."

It's not that singles can't afford to give. The Chronicle of Philanthropy reported that in the United States, nearly 600,000 single people with no children have US$1 million or more in wealth.

Maybe charitable organisations think single people just don't care about making a difference. To find out, I asked a group of single people what they would like to leave as their legacy. I was interested in anything single people were contributing or hoping to contribute: financial or otherwise, large or small.

"Retiring Solo" author Lori Martinek of Scottsdale, Arizona, has a foundation that will distribute all her assets, when she dies, "to financially disadvantaged women who want to create financial independence by starting their own business."

A 34-year-old single woman from New York, who's an artist, contributes to a scholarship fund for students at her college; she told me she dreams of creating a public mural. When a new animal shelter opened in her town of Bellingham, Washington, Kristin Noreen, an environmental consultant, commissioned an artist to build a bike rack to adorn the entrance.

A 41-year-old single woman from Houston has a trust that will fund family-planning services for women, as well as educational scholarships for young single women with no children. Cox-Brown also contributes to women's education. When she dies, she says, all her money "will go to charities that work to improve safety in cities at night." Environmental causes are designated in the will of Ilona, a 34-year-old single woman who is a librarian from Germany. A 51-year-old in Ohio hopes to create a foundation to benefit "nonhuman animals, both domesticated and wild." Karen Gritter, a 54-year-old from Michigan, would like to set aside land for a nature preserve.

Each year Meghan Cody, a 38-year-old clinical psychologist in Atlanta, trains about 15 future therapists. Many other educators and therapists also described their legacy as the difference they are making in the lives of their students or clients. Other singles are devoted to the children of their relatives and friends.

Asked about philanthropy for single people, Alicia Rosenthal, a 65-year-old in Los Angeles, said she would like to give to a group "dedicated to making sure rights and obligations of a citizen have nothing to do with marital status."

Kendra Heath, a 67-year-old from Santa Rosa, California, wants to "set up a foundation to help single parents get into their own homes at affordable prices." Leslie Pardue, a 56-year-old from North Carolina, said that "a good use of funds would be for health insurance for singles who cannot obtain it any other way and in-home support for elderly singles who need help to live independently."

As for me, I've long fantasised about starting a Foundation for the Empowerment of Single People that would support research, writing, reporting, advocacy and creative projects devoted to myth-busting, consciousness-raising and social justice for singles.

Maybe someone would propose a study to elucidate the disconnect between the stereotype of single people as selfish and the reality of their giving ways.