Lonesome George was the last member of the Pinta Island giant tortoises, the Chelonoidis abingdonii, most recently of Santa Cruz Island off the Republic of Equador. He died in 2012 at about 100 years old. You might say he left his genes to science.
Lonesome George in 2008, Arturo de Frias Marques, Wikipedia
George was moved from the island of Pinta in 1971, where he was identified as the only living Pinta Island tortoise. The island had been overtaken by feral goats who demolished the tortoise population on the island, so for safety, George was moved to the Charles Darwin Research Station on Santa Cruz Island, where he spent the remainder of his life. One hundred years is not considered that long for a Pinta Island Tortoise, as some lived as many as 150 years.
Perhaps George's life was cut short by loneliness; his autopsy revealed he died from 'natural causes.'
While at the Research Station, George did mate with a few females from closely related tortoise species, but their offspring either never hatched or never developed.
The Pinta Island tortoise is the longest lived vertebrate, so is of special interest to research. Spanish researchers reporting in Nature Ecology & Evolution have reported their findings on Lonesome George's genes, specifically those related to longevity and disease, and they discovered that the Pinta tortoise had many genes in common with some humans - longevity genes for one. Other genes connected with longevity in the giant tortoise, such as immune system genes and tumor suppressing genes, were not commonly found in humans.
You may wonder why a giant tortoise species with powerful immunity and longevity genes is now extinct. Thousands of years ago giant tortoises were found on virtually every continent on planet Earth, but they were eradicated by man, who enjoyed eating tortoise as much as animals. Now, like many other protected animal species, their numbers are few, and almost all giant tortoises live in some kind of captivity, away from prey - human or animal.
Though Lonesome George did not leave us any progeny, at least not in the last 40 years, his legacy will live on, as scientists learn more about his species from his genes. More large tortoises closely related to the Chelonoidis abingdonii are being brought to Pinta Island again, now that the goats have been removed. Hopefully, they will breed and support the growth of more giant tortoises.
Lonesome George on display, Charles Darwin Research Center (Wikipedia)
Lonesome George's body is preserved and on display at the Charles Darwin Research Station, Santa Cruz Island.