Nature's glowing wonders

(Clockwise from top left) Bioluminescence in the ocean, the Singapore jumping spider, the fluorescent frog and corals glowing in rainbow hues.
(Clockwise from top left) Bioluminescence in the ocean, the Singapore jumping spider, the fluorescent frog and corals glowing in rainbow hues.PHOTOS: COURTESY OF EDITH WIDDER, LI DAIQIN, AGENCE FRANCE-PRESSE, JORG WIEDENMANN
ALGAE: This photo of bioluminescent algae was taken in Tasmania's Preservation Bay. The natural phenomenon is caused by phytoplankton known as Noctiluca scintillans or "sea sparkle" which thrives in calm, warm sea conditions.
ALGAE: This photo of bioluminescent algae was taken in Tasmania's Preservation Bay. The natural phenomenon is caused by phytoplankton known as Noctiluca scintillans or "sea sparkle" which thrives in calm, warm sea conditions.PHOTO: FACEBOOK PAGE OF JIM CHATWIN PHOTOGRAPHY

The first naturally fluorescent frog to be discovered made the headlines last week, but this animal does not stand alone in the spotlight: some spiders use fluorescence to find love, while vampire squids squirt out clouds of light to befuddle predators. Here are some of nature's glowing wonders.

ANIMALS GLOW IN DIFFERENT WAYS

In fluorescence, molecules absorb light of one colour and emit light of a different colour. This emitted light, with its modified colour, is visible only while the stimulating light is turned on, so you cannot see fluorescence in complete darkness. In phosphorescence, the chemical reactions take longer to emit light, so a glow remains after the light has been removed. In bioluminescence, plants and animals create their own light.

GLOWING PLANTS, ANIMALS MADE BY SCIENTISTS

 


PHOTO: NUS

Scientists can produce their own glowing plants and animals too, such as these made-in-Singapore fluorescent zebrafish. They normally sport silver and black stripes, but can be made to glow red, green, orange and yellow with the help of jellyfish and anemone genes.

FLUORESCENT FROG


PHOTO: AGENCE FRANCE-PRESSE

This fluorescent frog was discovered recently in Argentina. Under normal light, the amphibian's translucent skin is a muted yellowish-brown with red dots, but when scientists shone an ultraviolet light on it, the frog turned a celestial green.

DEEP SEA JELLYFISH


PHOTO: COURTESY OF EDITH WIDDER

An image of an abundant deep sea jellyfish, photographed by its own bioluminescence.

JUMPING SPIDER


PHOTO: LI DAIQIN

The Singapore jumping spider uses ultraviolet reflectance and UV-induced fluorescence to communicate during courtship rituals.

FIREFLIES


PHOTO: GIORGIO MARGARITONDO

Fireflies use light flashes to communicate. Scientists found that fireflies control oxygen distribution to light up their cells. This microimage shows larger cell channels branching into smaller ones, supplying oxygen for a firefly's light emission. The smallest channels are 10 thousand times smaller than a millimetre.

CORALS


PHOTO: JORG WIEDENMANN

Corals glowing in rainbow hues have been found in the Red Sea's deep-water reefs, surprising researchers because their shallow-water counterparts in the same reef contain only green fluorescent pigments. Many corals at depths of over 50m have been found to glow in colours ranging from yellow to red.

BIOLUMINESCENCE IN THE OCEAN


PHOTO: COURTESY OF EDITH WIDDER

Most bioluminescence in the ocean is blue, but there are exceptions such as the yellow bioluminescence of some pelagic worms. Also shown (clockwise from worm in yellow) are the squid, the Northern krill, the scaleless black dragon fish and the deep sea jellyfish.

CATSHARKS


PHOTO: J. SPARKS, D. GRUBER AND V. PIERIBONE

This photo is of a biofluorescent chain catshark. Researchers found that catsharks are not only able to see the bright green biofluorescence they produce, but that they increase the contrast of their glowing pattern when deep underwater. Fluorescence makes catsharks more visible to neighbours of the same species at the depths that they live and may aid in their communication.

SCORPIONS


PHOTO: MICHAEL WEBBER

Using ultraviolet light that causes scorpions to fluoresce a ghostly glow helped researchers discover an intriguing new scorpion in Death Valley National Park in the United States.

A version of this article appeared in the print edition of The Straits Times on March 24, 2017, with the headline 'Natural glow'. Print Edition | Subscribe