The new findings challenge the theory that beach cusps are caused only by patterns in water movement.

I would toss a coin now as to why there are beach cusps."

The theory has two main points that seek to explain the formation of regularly spaced beach cusps.

Beach cusps are rhythmic shoreline features formed by swash action.

Morphological evolution of beach cusps and associated swash circulation Patterns.

This is one of those most probable state explanations, and may be compared with what has been said about meanders and beach cusps.

Beach cusps are shoreline formations made up of various grades of sediment in an arc pattern.

"Beach cusps are interesting but they are not the ultimate goal," Dr. Werner said.

Although the origin of beach cusps has yet to be proven, once cusps have been created they are a self-sustaining formation.

There are a number of theories as to why beach cusps are formed but currently, there are only two explanations with any real credibility.

On dissipative beaches cusps are usually formed by nearshore cell circulation systems, and may be associated with longshore periodic bars.

The model indicates that the typical swash pattern on beach cusps is three-dimensional, with wave uprush diverging at the cusp horns resulting in concentrated backwash streams in the embayment.

Though they can be subtle enough to escape the notice of bathers splashing in the surf, these beach cusps have long fascinated scientists, who have yet to figure out for sure exactly how they form.

So far, the strongest indication that self-organisation, rather than edge wave motion, is responsible for beach cusps has been provided by a study conducted on Pearl Beach (New South Wales, Australia).

Cellular automata models for the development of coastal geomorphological features This strand of research builds on my involvement with the Ph.D. work on beach cusps mentioned in the Research History section.

Although the more generally noticed constructional shoreline features are the large sand and shingle formations, interesting minor features are to be observed on many beaches, among them beach cusps and sand bars, for the formation of which little or no longshore drift is necessary.

Essentially what this means is that there are a regularly spaced series of peaks and troughs along the length on the incoming wave that are caused by its interaction with the standing edge waves and it is these that caused the development of beach cusps.

Scientists from Washington State University in Pullman and Scripps Institution of Oceanography in La Jolla, Calif., have made measurements that raise new questions about a widely accepted theory about the formation of beach cusps, regular undulations in the sand that appear as if by magic on many beaches.