<https://factrepublic.com/31-rare-facts-about-animals-birds-that-have-gone-extinct-from-earth/#webpage>
<http://schema.org/description>
"1. The last Kauaʻi ʻōʻō (now extinct) was male. Its song was recorded in 1987. It was recorded singing a mating call, to a female that would never come. It died in 1987 as well."
<https://factrepublic.com/31-rare-facts-about-animals-birds-that-have-gone-extinct-from-earth/>