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Giraffes' Long Legs Boost Energy Efficiency, Save Food

11/3/2025

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Summary

Story summary

The University of Pretoria study finds giraffes' long legs reduce the energy cost of pumping blood to the head.
Giraffes allocate about 16% of their energy to heart function, vs. 21% for a hypothetical long-necked, short-legged animal.
The energy efficiency helps giraffes thrive and saves over 1.5 tonnes of food annually.
Giraffes face drinking-water challenges because of their posture.
The study notes neck length is limited by heart energy costs.

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Story summary

The University of Pretoria study finds giraffes' long legs reduce the energy cost of pumping blood to the head.
Giraffes allocate about 16% of their energy to heart function, vs. 21% for a hypothetical long-necked, short-legged animal.
The energy efficiency helps giraffes thrive and saves over 1.5 tonnes of food annually.
Giraffes face drinking-water challenges because of their posture.
The study notes neck length is limited by heart energy costs.