Like Teenagers on Vacation

Written on |

Light pollution can impair crickets’ reproductive process and threaten their survival.

A joint study conducted by researchers from Tel Aviv University and the Open University of Israel revealed that exposing male crickets to artificial light at night (ALAN) can impair their activity cycles. According to the researchers, nocturnal chirping is the male’s way of calling females to come and mate with him, and its disruption can interfere with reproduction processes and even endanger the entire species. Previous studies worldwide have shown that light pollution is harmful to many species of animals and plants. The researchers call for reducing ALAN as much as possible to enable coexistence in the night environment.

Humans are Driving Away the Darkness

Keren Levy of the School of Zoology and the Steinhardt Museum of Natural History at Tel Aviv University explains: “The distinction between day and night, light and darkness, is a major foundation of life on earth. But humans, as creatures of the day who fear the dark, disrupt this natural order: they produce artificial light that drives away the darkness and allows them to continue their activities at night.”

Levy explains that today, more than 80% of the world population live under light pollution, and the overall extent of artificial light at night rises by 5% every year. This negatively impacts the environment and affects natural behaviors that have developed over millions of years of evolution. The artificial light at night affects the length and quality of sleep of many animals, leads to high mortality, and changes the activity cycles of many creatures. For example, dung beetles, that navigate using the Milky Way, lose their way when light pollution increases; sea turtles hatchlings seek the brightest surface in sight – supposedly the sea, and reach the nearby promenade instead; to mention just two of many examples.

Off-Tune Crickets

In the current study the researchers examined the impact of light pollution on the field cricket, a nocturnal insect whose chirping can be heard during the nights of late summer – when males call for females to mate with them.

Prof. Amir Ayali, also from TAU’s School of Zoology and the Steinhardt Museum of Natural History, explains, “In nature, crickets exhibit a very regular cycle of activity. Chirping behavior, calling for females, occurs at sunset and during the night, ending in the morning. We exposed field crickets to different levels of lifelong ALAN and observed its impact on two fundamental behaviors: chirping and locomotion.”

The researchers monitored dozens of crickets that were exposed throughout their lives (from egg to adult stage) to four types of light conditions. They found that crickets whose light-dark cycle is disrupted behave like teenagers on vacation: active or asleep according to their own inner clock or lacking any rhythm whatsoever.

“In fact,” adds Keren Levy, “light pollution induced by humankind impacts the field cricket and evokes loss of synchronization within the individual, on the population level, and between the population and the environment. Our findings on ALAN-induced changes in calling song patterns may possibly impair female attraction and reproduction in this species. Our results are in accord with many other studies demonstrating the severe impacts of low levels of ALAN on nature.”

Levy urges us all to help protect our environment and surroundings by turning off the lights in our backyards, on the terrace, in parking lots, and wherever possible: “Help us bring the night and the milky way back into our lives and enable nightly coexistence with the creatures around us.”

The study was led by Prof. Amir Ayali and Keren Levy of the School of Zoology and the Steinhardt Museum of Natural History at Tel Aviv University and Prof. Anat Barnea of the Department of Natural and Life Sciences at the Open University. Yoav Wegrzyn from Prof. Ayali’s laboratory and Ronny Efronny also took part in the study. The paper was published in Proceedings of the Royal Society B, and also mentioned in Nature.

Featured image: Prof. Amir Ayali and a small friend (Photo: Jonathan Blum)

Related posts

Outstanding Navigators, both Night and Day

30 May 2022

Big Brains Helped Large Animals Survive Extinction

19 May 2022

How are the Birds Coping with Climate Change?

25 April 2022

Why do Locusts Form Destructive Swarms?

17 February 2022

How Can We Boost Our Fight Against Marine Plastic Pollution?

24 January 2022

Over the Past 1.5 Million Years, Human Hunting Preferences have Wiped Out Large Animals

30 December 2021

How Do Bats Get Street-Smart?

24 November 2021

Revisiting the Tel Aviv Zoo

12 November 2021

Seahorses – Slow, but Fierce

7 October 2021

Why Do We Squabble Over The AC?

5 October 2021

A House is Not a Home Without a Pet

4 October 2021

Where Have All the Birds Gone?

11 August 2021

Tel Aviv Bats Have More Fun

22 July 2021

Bats ‘Social Distance’ Too

6 June 2021

Time Flies and So Do Bats

1 June 2021

When One Becomes Three

20 May 2021

Victoria

Tok Corporate Centre, Level 1,
459 Toorak Road, Toorak VIC 3142
Phone: +61 3 9296 2065
Email: office@aftau.asn.au

New South Wales

P.O. Box 4044, Maroubra South,
NSW 2035
Phone: +61 418 465 556
Email: davidsolomon@aftau.org.au

Western Australia

P O Box 36, Claremont,
WA  6010
Phone: :+61 411 223 550
Email: clivedonner@thelinqgroup.com