the.com/egg tooth
A baby's tiny demolition tool, built only to escape, then deleted.
means The small, hard, temporary protrusion on the beak or snout of a hatching bird or reptile, used to break through the eggshell and shed soon after.
from A plain English compound, exactly what it says: a "tooth" found on an "egg"-bound creature. The naming follows the descriptive logic naturalists love — though it's a bit of a misnomer for birds, whose egg tooth is a hardened cap of keratin rather than true dental tissue. Reptiles, by contrast, often sport a genuine little tooth-like point. The term took hold in zoology as a tidy label for this one-use hatching tool.
- single use
- Falls off days after hatching, never seen again
- not a tooth
- It's a hard calcium bump, not real enamel
- widespread
- Birds, reptiles, and some amphibians all grow one
- the job
- Cracks shell from inside in a process called pipping
- monotreme twist
- Even egg-laying mammals like platypuses have one
chicken egg tooth — small hard projection on chick's upper beak, sheds within days after hatching
snake egg tooth — specialized tooth on snake's rostral scale, used to cut through leathery egg shell at hatching
platypus egg tooth — monotreme's temporary tooth-like structure on snout, helps break through leathery egg membrane