That’s because too many of those Spirit probe photos show mechanical debris strewn across the sands as well as building foundations, structural timbers and the like. Try doing a google search on ‘pia04995’ and download the hires (25mb) TIF version of the NASA image which turns up and check out the lower right corner area of the image.
OK. Did that. Looked as directed at the lower right part of the picture...
I see no evidence of ancient Martian life, other than a apparently discarded 2008 Obama campaign button.
And we all know how “intelligent” that turned out to be.
I see rocks.
And sand.