Tragedy struck at Lincoln Park Zoo as Bana, a cherished 29-year-old western lowland gorilla, breathed her last this week, the facility announced on Thursday; born in Brookfield Zoo in 1995 before making her way to Lincoln Park in 2010, this beloved primate succumbed to congestive cardiac failure and was humanely euthanized on Tuesday after a battle with bronchopneumonia which made the full recovery impossible, a bitter pill to swallow for the dedicated staff who cared for her.

Bana, who rose to prominence as the dominant female in the zoo's gorilla troop, which includes her progeny and other members, became a well-known figure for her active participation in the zoo's cognitive touch screen program, where she often ensured she was the first in line to engage, details emerging from a Block Club Chicago report.

According to ABC 7 Chicago, the zoo staff, who had grown fond of Bana's nature as a great mother and her tolerance for the playful exuberance of the youngsters in her group, followed a practice that allowed the remaining gorillas a chance to view her body post-euthanasia, which is akin to the customs they might observe in the wild.

Jill Moyse, Curator of Primates at the zoo, reflected on Bana's influence in an emotional commendation, "Bana has left an undeniable mark on the hearts of zoo staff, volunteers, and visitors, and played an important role in her own troop," demonstrating that she wasn't only an exceptional maternal figure, but a notable individual in her species which is, sadly, listed as critically endangered by conservation standards, according to sentiments she shared with Block Club Chicago.

It is a sobering reminder of the leads captivated within zoo walls may reach ends similar to Bana's even while they serve as ambassadors for their wild counterparts; such western lowland gorillas are documented to potentially reach ages of up to 35 in the wild and 55 in protected environments like zoos, a statistic brought to light by Block Club Chicago.