The origin point: The first case of insects being used to point to a killer dates to the 13th century, and the murder of a farmer in rural China.

The frontispiece of Charles Baudelaire’s Les Fleurs du Mal (The Flowers of Evil) features a decaying skeleton by artist Félix Bracquemond. The anthology includes the poem Une Charogne (A Carcass; 1857). (Courtesy The Elisha Whittelsey Collection, The Elisha Whittelsey Fund, 1962, The MET)

Investigators of the time could tell that the man had been murdered with a sickle, but in a village full of rice farmers and sickles, it was proving impossible to tell which one, the Chinese physician and death investigator Sung Tzhu writes, in his 1247 book Hsi Yüan Chi Lu (The Washing Away of Wrongs).

Since searches and questioning had failed, the local judge decided to try a different tack. He called upon all the rice field workers to lay their sickles on the ground. One began to attract flies. Hordes of them.

Confronted, the owner of the sickle confessed. This case is said to mark the earliest point in the history of forensic entomology.

Art: By the time of the Renaissance, with its growing fascination with anatomical studies of the human body, elements of forensic entomology were showing up on canvas.

Take the woodcut series The Dance of Death by the 16th century German artist Hans Holbein the Younger. The macabre visuals depict Death as a skeletonised individual paying surprise visits to all kinds of people — a pope, a physician, a ploughman, a knight, a sailor.

In one revelry-filled depiction, skeletons dance and play a drum around a corpse, as tiny snake-like creatures dangle around their heads, necks and limbs. “Such artwork accurately depicts the insect-mediated pattern of body mass reduction, particularly the early skeletonization of the skull and the reduction of internal organs, with large parts of the skin left intact… Close observation of decomposition of human corpses built the basis for these figures,” writes German forensic biologist Mark Benecke, in a paper on the history of the field, published in Forensic Science International in 2001.

Poetry: Bugs feasting on the dead and decaying inspired the French poet Charles Baudelaire’s Une Charogne (A Carcass; first published in 1857). Amid a growing Romantic movement in which the arts focused on Nature, the self, and the lives of everyday individuals, the poem offers a raw and graphic exploration of death as a natural force, as a man describes a decaying body to his lover:

And the sky was watching that superb cadaver /

Blossom like a flower…

True crime: Around this time, the French physician Dr Louis François Étienne Bergeret used the life cycle of bugs to crack a case wide open, in the first such case on record.

The insect samples had been collected from the mummified remains of an infant, found stashed behind the chimney of a home in Paris, in the 1850s. Dr Bergeret’s analysis of the insect remains led him to ascertain time of death at approximately seven years before the tiny body was found.

This timeline was used to arrest the previous tenants of the house. Investigators began to question neighbours about their memories of the tenants in this period, just before they moved, and it emerged that the child, possibly born out of wedlock, had been buried alive. The woman responsible and her lover were convicted of murder.

Evolutions: From the 1890s on, small, scattered research projects were investigating the life cycle of insects and their relationship with decomposition, in Canada, the US, Sweden, France, the UK and Germany.

By the 1990s, advances in molecular biology, DNA and RNA analysis were boosting this field, and the understanding and study of forensics overall, says Jonathan Parrott, a forensic entomologist and assistant professor at Arizona State University.

Over the past two decades, forensic science departments around the world, including in India, have been working with cadavers of pigs, dogs and chickens to build developmental data and identification markers for different species of insects.

“It is still a fairly niche field. But what’s exciting is that it is greatly collaborative. From generation to generation of scientists, we’re building a foundation,” Parrott says.

In India: Forensic entomology here at home can be dated to the colonial era and the work of police surgeon S Coull Mackenzie in the 1880s.

In more recent years, Pankaj Kulshrestha and H Chandra, who worked with the Medico Legal Institute of the police department of Bhopal, were among the first to study how local species of blowfly may be used to determine time of death. Their paper was published in the American Journal of Forensic Medicine and Pathology in 1987.

Proponents of this field today include Devinder Singh, pro-vice chancellor and professor at Chandigarh University, who has trained in the lab of pioneering forensic entomologist Bernard Greenberg at the University of Illinois, and has worked with the government of India’s department of science and technology to create baseline data on carrion insects for the Punjab region. Since then, more research has been undertaken in various regions, but the country is lagging when it comes to awareness and application in criminal cases, Singh says.