Comparison of the testical, breast, and genitalia sizes of the great apes : r/Damnthatsinteresting

While many animals pant or sweat to cool down, it turns out Echidnas instead opt to blow snot bubbles and perform bellyflops : r/Awwducational

Size matters: Boar taint in relationship with body composition and testis volume measured by magnetic resonance imaging - ScienceDirect

Infidelity Leads to Large Testicles, Science

Beyond Testicles and Dads: 5 Legit Studies of Male Gear

Solved Name LAB EXERCISE Comparative Base: Apes and Humans

Tiny Genetic Differences between Humans and Other Primates Pervade the Genome

Why Did Humans Evolve Big Penises but Small Testicles? — Gayety

Sexual Dimorphism - Anthropological Musings and Concepts

Size of a chimpanzee brain compared to one of its testicles : r/pics

The aorta in humans and African great apes, and cardiac output and metabolic levels in human evolution

Beyond Testicles and Dads: 5 Legit Studies of Male Gear