Goose That Lays Eggs With Pitch-Black Yolk Leaves Experts Baffled

There are plenty of strange spectacles that surface on social media every day--but a couple of pictures of extremely black goose egg yolks left even scientists scratching their heads.

The pictures, shared on Chinese social media by a man identified only as "Zhu," who hails from China's Hangzhou City, created quite the stir. The pictures and video clips shared show a pair of white eggs being cracked open and the inner substance turns out to be tar-black yolks, according to Unexplained-Mysteries.

Zhu claims that the eggs came from a goose on his friend's farm and the bird has produced plenty of regular eggs earlier. He said it was pretty strange that this batch just stood out because of the yolk. Zhu added that the eggs were otherwise normal and the smell also didn't indicate anything amiss. The eggshells reportedly bear no signs of rot.

"These geese are all raised freely. When mulberries fall to the ground, they run to eat them. They contain melanin, so it may also be caused by eating too much mulberry, but this explanation is not particularly reasonable, so I am not sure, in short, it is quite strange," a person wrote.

The pictures went viral on social media, with several people speculating whether the goose was special or was on a mulberry diet, which can potentially boost melanin production, that produced such eggs. Zhu didn't buy into the idea because there are no mulberry plants on the farm. A person even wondered if the goose had "ingested some ink."

A user knowledgeable about poultry production came on board to give his opinion. He said that it wasn't for environmental pollution because the eggs did have a normal smell. He argued that it could be due to a "natural pigment."

Zhu, however, said in the video that the geese were raised for grazing on the farm and when some mulberry trees fell, they would come in numbers to feed on them. The mulberry fruits are purple in color when ripe and when the geese eat them in a large quantity, the yolk turns black. However, there is no definitive evidence as to why the yolks appeared extremely dark.

The Zhejiang Institute of Agricultural Sciences reportedly showed interest in conducting in-depth research on the strange appearance of the egg yolks.