Summary

Utilizing humor and fun visual animations, Phoebe A. Cohen answers the question all viewers wish to know the answer to: how to fossilize themselves to fame! In the span of five minutes, Cohen provides a basic, short and sweet overview on how the human body fossilizes overtime and what is needed for our perfect preservation.

Why watch this video?

• Do you wonder what sort of environments it takes for the natural preservation of your body?
• Have you ever wondered how decomposition has been stopped by natural means?
• How exactly does the human body become fossilized?

Key terms

Amber-preservation: typically occurs when a body is preserved by amber (hardened tree-sap) which can lead to preservation for millions of years. Such form is typically limited to insects and very small animals.

Lithification: general term for the overall process in which accumulated material (loose sediment typically) hardens into rock, through two processes called compaction and cementation.

Permineralization: a process that takes during decay; in which the soft parts of the body (i.g. skin, fat) decay away while bones become saturated with minerals carried within water environments. These minerals fill in pores/empty spaces of the bones to form an internal cast.

Loose ends

Little to no oxygen is identified as crucial for the success of preservation, as the lack of oxygen slows down the rate of decay. How and why?

This was not mentioned by Cohen, but it is rare that the skeletons of soft-bodied animals (which yes, includes us!) is extremely rare thanks to the rapid rate in which decomposition occurs (immediately after our heart stops beating). For our bodies to be fossilized, it is required it is protected from decomposition. The lack of oxygen inhibits insect activity and most activity by decomposer organisms (microscopic ones such as bacteria and fungi), resulting in a slower breakdown of the biological matter as little to no decomposition occurs.

What did Cohen mean by “the bone being saturated”? What is an internal cast?

Most fossilized bones undergo the process of permineralization, in which the process occurs typically in environments where the water contains minerals such as calcite, iron, and silicia. Bone is a highly porous material (meaning there is plenty of holes/gaps/space to be filled). In an underwater environment, the water saturates the bones with its minerals which fills the holes and form a material similar to cement (hence internal cast, because it is not encompassing the bone but it is filling in little bits and pieces within the bone). 

Wait, so what’s the difference between lithification and permineralization?

Lithification is a process separate from (but closely related to) permineralization, a process involved in the creation of sedimentary rocks. The loose sediment is compacted by burial, forcing water (connate fluids aka the original water upon the sediment’s deposit) and air out of the pores of grains – these grains are then cemented together through a chemical process, in which the minerals deposited by water in the pores.

Permineralization refers to minerals specifically as the material filling in the voids/spaces in bone cavity, it is through the filling of the pores with this mineral water that upon evaporation, the excess minerals from the water is deposited on cell and tissue. This is called an “internal cast” that preserves patterns and the original cellular structure of the remains, though the actual original matter of the fossil itself is no longer there.

Self-Test Questions