Good ol' Thunderbolts-come-from-Jupiter Pliny the Elder, the most trustworthy source there is.

This is known hoax, the source is a lie and the real source is not trustworthy in a scientific sense.

What is actually on Wikipedia and by the person claimed as a false source is this:

Funeral rites in animals

While grief is common to many animals, funeral rituals are not. However, they are well documented in African elephants.[14]

Ronald K. Siegel writes that:

one cannot ignore the elaborate burying behaviour of elephants as a similar sign of ritualistic or even religious behaviour in that species. When encountering dead animals, elephants will often bury them with mud, earth and leaves. Animals known to have been buried by elephants include rhinos, buffalos, cows, calves, and even humans, in addition to elephants themselves. Elephants have [been] observed burying their dead with large quantities of food, fruit, flowers and colourful foliage.[15][clarification needed]

Both wild and captive chimpanzees engage in ritualized behaviors at the death of a group member. These behaviors begin with group or individual silence, which may last for hours and followed by behaviors such as distinctive vocalizations; grooming the carcass; solemn visitation and gazing at the carcass by group members; displays; and lamentation-like whimpers or hoo-calls of distress.[6]

Attention to the dead is not unique to elephants or chimpanzees. Dolphins have been known to stay with recently deceased members of their pod for several days, preventing divers from getting close.[8] However, the reasons for this remain obscure. While scientists can observe their actions, the thought processes that motivate them are beyond current study.[16]

Tahlequah (a.k.a. J35), a female orca, carried the carcass of her newborn infant for 17 days.[17]Whether this was a "tour of grief" or merely instinct is debated.[10]

Crows and other corvids also seem to participate in funeral-like ritualistic behavior, including gathering around and holding vigils over the carcass.[9][

"Observations by Pliny the Elder"... I love the fact that someone is still reading ancient ass proto-science, but it really really has to be taken with a grain of salt.