article_snippet.sent: a new technique has allowed researchers to look millions of years into the past to see how these once elaborately decorated shells would have once looked.
article_snippet.sent: these once elaborately decorated shells have bleached over time, like the one labelled A, but under ultraviolet light traces of pigment still in these once elaborately decorated shells are revealed, labelled B, allowing their colours to be reconstrcuted (C)
article_snippet.sent: Dr Jonathan Hendricks, a paleontologist at the San Jose State University who led the research said: 'Original coloration patterns — if not the actual colors themselves —sometimes become visible when fossil shells are illuminated with ultraviolet light, which causes formerly pigmented regions of the shell to fluoresce. '
article_snippet.sent: Once a specimen has been photographed under UV light, a specimen is possible to use photoediting software to reconstruct the original shell coloration pattern. '
article_snippet.sent: Dr Hendricks used the ultraviolet technique to examine a range of fossilised shells that were discovered in the Cibao Valley of the northern Dominican Republic.
article_snippet.sent: This image shows three of the fossil shells studied by the scientists as the scientists currently appear without colour .
article_snippet.sent: Scientists used UV light to reveal tiny traces of the pigment left in the shell and the patterns Scientists once had .
article_snippet.sent: However, identifying these can often be tricky as over time the bright pigments in the shells fade.
article_snippet.sent: Exposing these to ultraviolet light causes any remaining organic matter in the shells - like pigment - to fluoresce.
article_snippet.sent: It is thought that these compounds in the shells oxidise over time and so light up when UV light is shined on these compounds in the shells.
article_snippet.sent: UV light allowed scientists to peer back millions of years to reconstruct shell patterns and colours as above .
article_snippet.sent: Clearly much more work needs to be done to better understand the compounds responsible for shell coloration. '
article_snippet.sent: That said, it seems that oxidation - caused either naturally by exposure of shells to sunlight over prolonged periods of time, or artificially by soaking in bleach for several days - plays a role in causing formerly pigmented regions of fossil shells to fluoresce under UV light, though the reason is not currently understood.'