Palaeontologist reveals insects' colourful past

Feb 27, 2013
Palaeontologist reveals insects’ colourful past
The iridescent jewel beetle Chrysochroa raja owes its colour to nanometre-size structures in its outer tissues and was used in fossilisation experiments to explain patterns in the fossil record of colour.

(Phys.org)—An international research team led by a University of Bristol scientist has explained the preservation of colours in fossil insects for the first time.

The discovery explains why colours change and why they are destroyed during fossilisation, revealing hidden gems in the insect fossil record that could help reconstruct the evolution of colours in insects.

The paper has just been published online in the journal Geology. The research will also be showcased at this year's prestigious Royal Society Summer Science Exhibition in London, from 1 to 7 July.

Many modern insects owe their brilliant colours to microscopic light-reflecting structures in their tissues, but the fossil record of these 'structural colours' is patchy. Even where these colours are fossilised, the original colours change during the fossilisation process.

Dr Maria McNamara, a Research Assistant in Palaeobiology from the School of , led a team of researchers from Yale University and University College Dublin which used a novel experimental technique to simulate high pressures and temperatures that are found deep under the Earth's surface.

The team used modern and discovered that they changed colour during the experiments due to changes in the chemistry and physical architecture of the colour-producing structures in their tissues.

Dr McNamara said: "Our results explain a big mystery in the field of fossil colour. By looking at what happens to structural colours in modern insects during fossilisation experiments, we can now say exactly why and how structural colours change during the burial process. Now we know what key events in the of sediments can cause colour change. This will help us to pin down which fossils show colours that we can trust, and which have been altered.

"Our results also provide compelling evidence for why certain types of structural colours - produced by complex 3D organic crystal lattices called 3D photonic crystals - aren't found in the . Rather than simply not being preserved, our experiments show that these structures are really tough and can survive the same burial conditions as other structural colours. This indicates that 3D , which are the most complex colour-producing structures known in nature, evolved extremely recently - within the last few million years."

Explore further: Aging white lion euthanized at Ohio zoo

More information: McNamara, M. et al. The fossil record of insect colour illuminated by maturation experiments, Geology.

Related Stories

Reading in two colours at the same time

Mar 09, 2011

The Nobel prize-winning physicist Richard Feynman once wrote in his autobiographical book (What do you care what other people think?): "When I see equations, I see letters in colors - I don't know why [...] And I wonder what t ...

Why are so many fairy-wrens blue?

Nov 01, 2012

(Phys.org)—Researchers have long tried to explain the enormous diversity in colour of birds, and a new study is giving insights into why the humble fairy-wren, a colourful Australian bird, is radiantly ...

Recommended for you

A vegetarian carnivorous plant

Dec 19, 2014

Carnivorous plants catch and digest tiny animals in order and derive benefits for their nutrition. Interestingly the trend towards vegetarianism seems to overcome carnivorous plants as well. The aquatic carnivorous bladderwort, ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.