Follow Mint Lounge

Latest Issue

Home > Smart Living> Environment > A colourful science tale of why animals change colours

A colourful science tale of why animals change colours

A new children's book explains the cellular and molecular mechanisms that allow animals – like the chameleon – to change colours

An illustration of two triggered Panther chameleons from the book. 
An illustration of two triggered Panther chameleons from the book.  (Ipsa Jain)

Listen to this article

Who hasn’t heard of the popular saying - ‘changing colours like a chameleon’? Depending on its surrounding, this cold-blooded reptile is believed to change its skin colour. However, that’s a misconception. The reason chameleons change colour is not to hide or blend in with the surroundings. Rather, it’s to show dominance when another chameleon enters their territory. 

Also read: A deep dive into science, but with a dash of humour and irreverence

Like chameleons, there are various birds, animals and sea creatures that display colours for a variety of reasons. But what causes them to change colour, and more importantly, what are the cellular and molecular changes that take place? A new book, titled Actually, Colors Speak, attempts to answer these questions along with an explanation of how we – humans – view colours. 

Aimed at high school students and adults who are “still young at heart”, the self-published illustrated book is a brainchild of Minhaj Sirajuddin, associate professor at the Institute for Stem Cell Science and Regenerative Medicine (inStem), Bangalore, and Ipsa Jain, a scientist turned illustrator who tells stories of science. 

While there are a lot of popular science books on wild animals and their behaviour, there aren’t many which explain what happens internally, when the animal changes colour, explains Jain.

What’s interesting is the book's narration. Instead of passive prose, the concept of colour and colours in living creatures is told in a conversational format between the most frequently used instruments used by naturalists and scientists – the binocular, camera and microscope. To make it relatable to young readers, the conversations use emoticons. "The emoticons articulate the expression and we thought it would be fun,” Jain says. The work on the book began in 2019. However, due to the covid-19 pandemic and challenges in getting the right publisher delayed its progress.  

To narrow down the focus of the book, Sirajuddin explains that they looked at animals which change colours within minutes. However, there are those who change colours gradually over a course of days to months. For instance, colours of juveniles and adults are vastly different in some species.

The orange-red pigments concentrated in centre of the cell gives cichlid fish the yellow hue.
The orange-red pigments concentrated in centre of the cell gives cichlid fish the yellow hue. (Ipsa Jain)

While the chameleon changes its colours to protect its territory and show its dominance, others use colours to either ward off predators or attract mates. For example, the book goes in great detail to show how a male cichlid fish changes from yellow to bright red to attract a female, by explaining the concentration of pigments in its cells that react to the light and display the mating colours. Birds are an excellent example of the latter. Male birds go to great lengths to showcase their colour plumage to make themselves attractive. 

Considering the complexity of the subject, especially cellular changes that take place in different species, the book is sprinkled with QR codes. These lead to stories and ideas that couldn’t weave into the script, Jain explains.      

One of the creatures that fascinated Jain – the glitter squid or bigfin reef squid – is a great example of how an animal changes colours beautifully. There is an amazing story about how the squid goes about it. “It's beautiful when you look it under the microscope but also when you see it change colour externally. But we couldn’t include that because we already had the octopus, which had a similar mechanism but slightly different. Then there was this amazing story of the Panamanian golden tortoise beetle, which changes its colour from red to golden by secreting liquid over its wings, which then interacts with the light to change the colour,” she says.  

Overall, the duo hopes that the book fascinates young readers and is used as a launchpad to dwell deeper into the subject. 

The book is available on the Notion Press website, and Price: 500, including shipping charges. 

Also read: A new children's book series highlights Kashmir's biodiversity

Next Story