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> Where is the quadratic part of the equation that limits the maximum size of a whale?

Muscle power output increases with cross section area, ~L^2, not with volume. The heart have no separate power unit. It relies on the same muscle walls that comprise its chambers to power itself.

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That just means the walls of the heart would need to grow thicker. Are they at the limit already?

Wall thickness increasing by x increases cross section/power by x^2, but also increases chamber volume/workload by x^3. So workload outruns available power. It's because of this people abusing steroids get heart failure eventually.

>chamber volume/workload by x^3. So workload outruns available power.

What do you mean by workload? Are you referring to the oxygen cost per stroke, or what?

Power demand. Volume pumped each cycle * (systolic pressure - diastolic pressure) / time.

Mate, I have no idea what you're saying, or how it's a constraint on size.

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