A jellyfish is unlikely to become a fossil because it lacks parts. (Use just one word for your answer.)
The correct answer and explanation is:
Answer: hard
Explanation (300 words):
Jellyfish are unlikely to become fossils because they lack hard parts. Fossilization is a rare process that usually preserves the hard components of organisms, such as bones, teeth, shells, and exoskeletons. These parts are more resistant to decay and environmental conditions, allowing them to survive long enough to be buried by sediment and eventually mineralized.
Jellyfish, on the other hand, are soft-bodied marine animals made mostly of water—up to 95%—and soft tissues. They do not have bones, shells, or any rigid structures. Because of this, their bodies decompose quickly after death, often before they can be buried in sediment or protected from scavengers and environmental damage. Without quick burial or preservation under special conditions, the chances of fossilization are extremely low.
Despite this, jellyfish fossils do exist, though they are exceedingly rare. These fossils are usually found in exceptional sedimentary deposits called Lagerstätten, where rapid burial and low oxygen levels help preserve even delicate soft tissues. In such rare cases, the outline or imprint of a jellyfish may be preserved in fine-grained sedimentary rock. Famous examples have been discovered in locations like the Burgess Shale in Canada and the Ediacaran biota in Australia.
The rarity of jellyfish fossils highlights the importance of hard parts in the fossilization process. Organisms with durable structures are far more likely to leave a fossil record, which is why our understanding of prehistoric life is biased toward animals with bones, shells, or teeth. Soft-bodied organisms like jellyfish, worms, and many ancient invertebrates are underrepresented in the fossil record because they decay rapidly and usually leave no trace unless very specific conditions are met.
In summary, the absence of hard parts in jellyfish makes their fossilization extremely unlikely, explaining why they are so rarely found as fossils.