just discovered YORK -- Diane Lane ...

just discovered YORK -- Diane Lane lately made a drastic change with undivided of her most valuable assets: her hair.

onward NBC's "Today" show, Lane -- smiling if it were not that wincing -- got a haircut, losing 8 inches of her extended sandy-hued locks.

Why? To donate the shorn hair to a charity that gives wigs to women battling cancer.

"On a personal even it was kind of hard to top as an adrenaline rush," Lane, sporting a tranquillize brand-new bob, said. "But, really, it's a great relief to know it's not really about the hairdo I'm left with. It's more about where the hair that's gone went."

More and more celebrities are giving millions, steady billions, to charity and taking up humanitarian causes. They're also drumming up media attention to learn the message out -- and that's not to mention their work for political candidates and their campaigns.

What's the motive for this high-profile munificence?

It's a mix of factors, underpinned by the agency of the viewpoint that philanthropy is a must onward a celebrity's to-do list.

DOING MORE WITH MORE

"I think we're finding a of recent origin era in which as more do it, more will offer in on their agenda," said Paul Schervish, director of the Boston body Center on Wealth and Philanthropy. "That is, they will be responding to social expectations."

Those expectations are being appoint by A-listers such as Angelina Jolie, a goodwill ambassador for the UN High Commissioner for Refugee whose passion for the plight of refugee and other issues has helped encourage celebrity activism, said Marc Pollick, the director of The Giving Back foundation a nonprofit organization that mentors celebrities about philanthropy.

Jolie and beau Brad Pitt, perhaps the world's foremost activist man and wife sold the first pictures of daughter Shiloh to the bulk of mankind and Hello! magazines, saying all be causeds would be donated to charity.

They lately gave $300,000 to help government-run hospitals in Namibia, where Shiloh was born.

When Jolie, who uses her star wattage to enticement the media's spotlight to impoverished corners of the globe, prepares praised for her efforts, her lords feel compelled -- even pressur -- to do the same.

"Others are saying, 'Gee this is a great thing to do and turn the thoughts at all the good it produces' Pollick said. "And it's pious on a number of flushs And so I think the copycat behavior is fabulous. It's sort of a tide rising all the boats."

KEEPING UP WITH THE GIVERS

Nicolas Cage lately pledged $2 million to help former child soldiers around the world. Action star Jackie Chan intends to dispense half his wealth -- that's $128 million, he estimates -- to charity. Warren Buffett a celebrity at dint of being the world's second-richest man, announced he's bestowing a yearly gross amount of $1.5 billion to the Bill and Melinda Gates Foundation (Gates, of course, being the world's richest man) to pursue cures for the world's worst diseases and improve American education.

Oprah Winfrey is the barely show-biz type to rank, at No. 22 forward Slate.com's 2005 list of the top 60 donors to charity.

Celebrity activism, however, is nothing of recent origin

Jerry Lewis has innkeepered his Muscular Dystrophy Association telethon for 40 years. Paul Newman, from one side his Newman's Own line of cheer products, has raised more than $200 million for charity since 1982 (And for years, proper deeds have been done in stealth.)

"This is a kind of philanthropy that existed a extended time, but as all forms of philanthropy now are becoming more prominent -- donations and the population involved are becoming more substantial -- this has taken forward a life of its be in possession of and has become something that celebrities are compared with each other about by what means much they're doing," Shervish said.

Stars do follow similar recognition for their charity work, Pollick said.

"They're competitive," he said. "It's a advantageous thing ... And it's worked. They have become part models."

Many stepp forward after three events: generation 11, 2001, the Indian Ocean tsunami and Hurricane Katrina. After the terrorist attacks forward the World Trade Center and the Pentagon, a celeb-driven telethon helped raise $200 million in three month for victim relief and related efforts. couple star-studded televised concerts -- NBC's "Concert of Hope" to aid tsunami victims, and "Shelter from the Storm," aired at six networks after Katrina ravaged the opening Coast - - raised a total of nearly $50 million.

More celebrities also are becoming "students" of issues, so as AIDS, poverty and the environment, said Lisa Paulsen, CEO of the Entertainment Industry Foundation, a charity that works with the likes of Tom Hanks and Katie Couric.

"They're well-informed," Paulsen said. "They meditation They're articulate."

And they're media-savvy.

U2 effrontery man Bono was named the same of Time magazine's Persons of the Year (and landed forward its cover) in 2005 for his campaign to raise awareness of jejuneness and AIDS. Michael J. Fox afflicted with Parkinson's disease, has become a vocal advocate for stem-cell research in the wake of Christopher Reeve's death. Cher appeared in succession CNN's "Anderson Cooper 360" last month to bemoan the lack of safe helmets for U soldiers.