The pickled animals, elephant dung and stained bed of previous years may seem like a hard act to follow, but the Tate is once again courting controversy with the 2008 Turner Prize.

Its curators today unveiled a female mannequin on a lavatory and a video of someone smashing crockery and likened the works to the tradition of still-life paintings by 17th-century Old Masters.

Found objects and video are the tools of the trade for the four artists picked this year.

One of them, Cathy Wilkes, 42, is a Glaswegian who gathered together a television, a sink with a single human hair and a pram and titled it She's Pregnant Again when she represented Scotland at the Venice Biennale in 2005.

This time, she has placed a mannequin on a lavatory next to two supermarket check-out counters. Four horse-shoes and bits of discarded wood dangle from wires attached to the mannequin's head. They appear to bear no relevance to the check-out counters on which the artist has arranged bowls and spoons, as well as empty jars with the remnants of food. Scattered across the floor are piles of tiles and broken pottery in a plastic bag.

Sophie O'Brien, one of three Turner Prize curators, saw deep meaning in the installation, explaining that the artist was “searching out the language of objects - things we overlook in our daily life” - and making us look at them with “fresh eyes”. She claimed that the artist had placed each found object with extreme precision.

Her colleague, Judith Nesbitt, the Tate's chief curator, added: “It's as if the narrative has been stripped away. You're left trying to make sense of the objects to each other and to ourselves.”

She applauded the artist for prompting “so many questions” from the viewer.

The shortlist also includes Runa Islam, 37, a Bangladesh-born video artist who explores “notions of truth and fiction, subjectivity and authorship”. Her three video pieces include Be the First to See What You See as You See It, in which a woman sits at a table laid for tea and proceeds to smash the objects by tipping them on to the floor. In another video, First Day of Spring, she filmed a group of rickshaw drivers after instructing them to sit and do nothing in a park.

The Tate's curators spoke of the artist's brilliant use of colour and light with the medium of film.

Further competition for the £40,000-prize comes from the only man on the list, Mark Leckey, 43, a video artist from London, who focuses on youth sub-cultures. His contribution includes a scale model of his studio alongside flickering slide images of it that hurt the eye.

Finally there is Goshka Macuga, 40, a Pole who is said to “blur the boundaries between artist, curator and collector” by laying out images of other artists' work alongside apparently random objects such as books and souvenirs, described by the Tate as “dramatic environments”. Her installation includes freestanding glass walls that look like a shower cubicle.

The Turner Prize has become the world's most provocative and prestigious contemporary art award but, for its critics, the 2008 selection once again confirms that Turner, the 19th-century painter, would be turning in his grave.

Given annually to a British artist under 50 “for an outstanding exhibition or other presentation of their work”, the prize is no stranger to controversy. Each year, it overlooks traditional artistry.

In 2001, it sparked a furore after Martin Creed won with a bare room containing a light that flickered on and off, and in 1998, Chris Ofili divided opinion after taking the prize for applying elephant dung to a Virgin Mary figure.

David Lee, the editor of the satirical art magazine The Jackdaw, was less than impressed by the latest shortlist. “These are the scrapings of the scrapings of the barrel,” he said. “This is nondescript work that's virtually indistinguishable from student work.”

But Stephen Deuchar, the director of Tate Britain and chairman of the Turner Prize jury, defended the choice: “The public is now not frightened by art that requires some investigation and whose meaning is not instantly clear.”

Dr Deuchar said: "Cathy's work is not always going to be comfortable for the viewer. It's like fragments of episodes in her life that we are not quite sure about. At some level, she's inviting us to share issues that are deeply personal, almost too personal ...

“One of the strongest visual features is the shop mannequin which has several attachments around her head. It is almost as if the mind is burdened with too many ideas.”

He summarised Leckey's art as “hugely invigorating”, Islam's as “exquisite” and Macuga as “not just an artist but an orchestrator”.

On the pavement outside Tate Britain, the Stuckists art group staged a demonstration at what its members derided as the “ghastly Turner Prize”. Its members were protesting at the Tate's promotion of conceptual art and its marginalising of figurative painting.

Charles Thomson, founder of the Stuckists, said: “The work is not of sufficient quality in terms of accomplishment, innovation or originality of thought to warrant exhibition in a national museum.”

He added: “The majority of artists in this country are figurative painters, yet none is represented.”

An exhibition by the shortlisted artists, which each year attracts up to 100,000 visitors despite the criticisms, will be staged at Tate Britain from today until January 18.

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