[@zhiyininbcn]

@zhiyininbcn asked the Naked Scientists:
   
Wonder why the perception of time-elapsing speed is related to the rhythm of heartbeat.  Animals don´t feel they age quicker.

What do you think?

[CliffordK]

I believe that heart rate is related to the size of the heart and the size of the animal.

So you might list heart sizes as:

Fruit fly
Mouse
Rat
Human
Elephant

So, the fruit fly's heart is smaller than an elephant, and beats faster than an elephant's heart.

The fruit fly also has a shorter lifespan and perhaps even a higher metabolic rate.

Everything would be more condensed in the fruitfly's month-long lifespan, but perhaps the tiny bug doesn't have the same temporal perception as we would, or the elephant.