Turtle Clock
A giant tortoise's heart is said to beat only about six times a minute — ours, sixty to seventy. If bodies count time in heartbeats, a tortoise's world may run at roughly one-tenth speed.
While you spent a whole minute hurrying, the tortoise has used only six seconds.
The Jonathan Conversion
Jonathan, the world's oldest tortoise, hatched around 1832. Enter your age to convert yourself into turtle time.
Elephant Time, Mouse Time
This clock is inspired by a famous Japanese book: Elephant Time, Mouse Time — The Biology of Size (1992) by biologist Tatsuo Motokawa. Its theme: the flow of time differs with body size.
Motokawa shows that an animal's time scales with roughly the quarter power of its body weight: multiply weight by 16, and heartbeat, breathing and lifespan all slow by half. A mouse's heart races over 600 beats a minute through a 2–3 year life; an elephant's beats about 30 times a minute across decades.
The book's most famous calculation: count a mammal's lifetime heartbeats and mouse and elephant both land near two billion. Measured by the clock of the heart, every mammalian life is the same length — some just run fast, others slow. Hence the leap: perhaps bigger, slower creatures experience time more slowly.
Turtles aren't mammals, so the math doesn't strictly apply — but slow metabolism, slow heartbeat and long life are the very architecture of slow time. For Jonathan at 190, a year may feel like five of our months. On rushed days, watch the turtle clock above. Only six seconds have passed.
Note: heart rates and subjective time involve estimates and hypotheses. No turtle has yet been successfully interviewed about clocks.
