"I'm a big fan of Coco," Barker said of the Toronto-born, Richmond, B.C.-raised Rocha, one of 50 famous faces featured in his new book "Models of Influence" (Harper Design).
"I believe that she will be seen as a supermodel of the era when we look back because of many things. Not just the fact that she's successful and she has many magazine covers and all the rest of it, but really how she's utilized social media — one of the very first models to understand that medium."
Barker, host of modelling competition series "The Face," said social media has played a pivotal role in further propelling the careers of models and other celebrities, translating to appearances in high-profile campaigns and fashion editorials.
"The designers and the editors and the photographers see who has the most likes, and hence, Kim Kardashian (and) Kanye West on the cover of Vogue; Kate Upton on the cover of Vanity Fair," said the former "America's Next Top Model" judge.
"You can say it may not just be that, but I think we all know it's playing a large part."
Barker draws on the archives of leading fashion photographers — including the late Richard Avedon, Irving Penn and Herb Ritts — for images to illustrate his profiles of noteworthy female models from the 1940s to the present.
Among those featured are one-name wonders Iman and Twiggy, '70s stars Jerry Hall and Lauren Hutton, supermodels Tyra Banks, Cindy Crawford and Naomi Campbell and modern-day phenoms Gisele Bundchen and Cara Delevingne.
St. Catharines, Ont., native Linda Evangelista — one of the leading supermodels of the '80s and '90s — is hailed by Barker for her strengths as a style chameleon. Toronto-raised Daria Werbowy — a Canada's Walk of Fame honouree — holds the record for opening and closing more fashion shows than any other model in history.
Many of the women have also parlayed their success into new areas, blazing trails and becoming entrepreneurs with their own beauty and fashion brands.
In some cases, their mere presence helped diversify the fashion landscape.
A notable example is the late Naomi Sims, the first black model to work for mainstream publications like Ladies' Home Journal, Life and the New York Times.
"(She) became the first African-American woman on a TV commercial in America — 1967. It's not that long ago, right? But the doors that it opened for people to actually see themselves for the first time and say: 'You know what? That could be me,'" said Barker.
"It takes women like that to push through and to change people's opinions."
Barker said he sees their ability to be spontaneous as a unifying factor among the famed models he profiled.
"When you look at someone or you're around someone and they're going to surprise you and you don't know in which way, that makes you nervous — but it makes you excited.
"It's freedom to be yourself. Some people have it and some don't. It's little to do with how perfect your facade is, which is one of the great reasons why, in many respects, some of the supermodels aren't the prettiest girl in the room or the prettiest girl of the time.
"But they speak to the moment because they're somehow in tune with how we're all feeling."
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