Scientists have unlocked new information about giant elephant birds: the largest birds known to science but, unfortunately, have gone extinct.

Upon analysis of the creature's reconstructed brain, scientists from the University of Texas at Austin revealed that these incredible avians were nocturnal and likely blind.

The findings were published on Oct. 31 in the journal Proceedings of the Royal Society B.

Reconstructing Elephant Bird Brains

From their reconstruction of the creature's brain, scientists found that the optic lobe or part that processed vision of the elephant bird was tiny. This discovery made them believe that the creatures were nocturnal and blind. 

These same traits are also present with the elephant birds' closest living relatives, the kiwis of New Zealand. 

This comes as a surprise because previous assumptions grouped elephant birds with other big, flightless birds such as emus and ostriches. However, emus and ostriches are most active during the day. They also have better eyesights than kiwis and, likely, elephant birds. 

"Studying brain shape is a really useful way of connecting ecology — the relationship between the bird and the environment — and anatomy," stated Christopher Torres, a Ph.D. candidate who led the study. "Discoveries like these give us tremendous insights into the lives of these bizarre and poorly understood birds."

For the study, the scientists looked at the skulls from two species of elephant birds. They used CT-imaging to create digital reconstructions called endocasts of the brains of the giant avians. The scientists also created endocasts of brains of the close living and extinct relatives of the elephant birds. 

Elephant Bird Extinction

The endocasts of the brains of the elephant birds also allowed the scientists to peek into the past, particularly the kind of habitat the creatures had before they disappeared on the surface of the Earth. From the endocasts, they were able to study the part of the brain responsible for processing the creatures' sense of smell. 

One of the skulls had a bigger olfactory bulb, for example, suggesting that the creature might have lived in a forest. Meanwhile, a smaller olfactory bulb is associated with grasslands. 

Elephant birds started dying out between 500 and 1,000 years ago. Scientists believe that their extinction was a mix of human meddling (hunting) and loss of habitat.