It has long been known that different materials require different amounts of energy to crack. (newscientist.com)
That's because males and females may require different amounts of energy to raise, or because one sex may be a better bet for passing on genes. (sciencemag.org)
Plants have different colors, which cause them to absorb different amounts of energy from the sun (the term «albedo» refers to the fraction of light reflected, i.e. how «shiny» something is). (realclimate.org)