BOSTON (AP) _ A new urban fashion these days is to be upwardly mobile - not just at work, but at play.

Hundreds of Boston area residents have taken with gusto to rock climbing in the midst of high-rises and highways.

''People's work presents one type of challenge,'' says Paul Niland, who runs the New England School of Moutaineering. ''Climbing presents another, which gets them to push themselves to their limits and try things they're not exposed to in their workaday world.''

Under Niland's leadership, Bostonians are clambering over rock formations behind a shopping mall, up the sheer stone wall of a highway overpass, and in an abandoned quarry.

''A lot of my friends are climbers,'' said Erika Ketelhohn, 35, an administrator at the Gray Herbarium at Harvard, ''and it's a great way to meet men.''

She said it wasn't easy getting up the courage to do her first climb last October.

''I was afraid of heights,'' she said. ''I nearly wimped out but I got to the top, and you feel like you've done something.''

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GRANDVILLE, Mich. (AP) - Debbie Smith says she can do without the skull and bones of a prehistoric elephant that were found on property she and her husband own.

''It doesn't matter to me'' what is done with the mastodon's bones, Mrs. Smith said. ''There's nothing we can do with them.''

The find ''can go right to the museum,'' she said.

Grand Valley State College archaeology Professor Richard Flanders said the bones are between 8,000 and 30,000 years old and are very well preserved.

''The teeth are almost pristine, there is no deterioration, fantastic,'' he said.

The bones were found Thursday on a lot where Mrs. Smith and her husband, Mark, are building a house for Linda and Ron Timmer.

''When I called my husband to tell him there was an elephant in our yard, he didn't believe me,'' Mrs. Timmer said. ''I'm a wreck.''

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