The "Mars Bone": Optical Illusion or Scientific Breakthrough?

The "Mars Thigh Bone"

Hailed by UFO enthusiast as proof that extraterrestrial life once existed on the red planet, a new image taken by the Curiosity rover appears to show what resembles a "thigh bone". NASA though remains unimpressed and maintains that wind erosion can make ordinary objects appear like objects we recognize. When the "face on Mars" first made headlines years ago, NASA was quick to point out that a trick of light led to the illusion. When seen from other angles and lighting, the face illusion disappears. Although some objects will retain their shape as they are clearly not just manifestations produced by light infraction, it does not follow that they are in fact what they appear to resemble. Despite this, it would be nice for scientific purposes if an analysis were done to rule out the possibility of a bone fragment. Whether Curiosity has this capability is questionable but it could at least identify a partial chemical composition. Does it contain a higher than expected amount of carbon or calcium? If so, this would be quite interesting.

In its early period, the red planet was likely covered by primordial seas. Not having a magnetosphere to protect it, solar wind stripped off most of the atmosphere and the planet dried up. During this time, it is possible some microbial life appeared but it is doubtful anything this advanced could have evolved. On Earth, multicellular creature only appeared after the Snowball Earth period. It wasn't until then that the first collagen molecules appeared. Collagen is the scaffolding that holds multicellular creatures together. Collagen requires oxygen and there simply was not enough before this time for multicellular creatures to develop. Since Mars lost its atmosphere before collagen or a similar molecule could appear, it is unlikely the bone structure is indigenous to the planet itself. However, this does not rule out the possibility that the bone came from another world. For all we know, a prior civilization brought it there and this is the remains of their lunch.