Colobus monkeys from the forests of Zanzibar have long been observed consuming charcoal, and not for nourishment, but as a functional strategy to neutralise the toxic alkaloids present in their leafy diets. This behaviour, documented by Struhsaker and Oates (1975) and later expanded on by Cooney and Struhsaker (1997), is a stellar example of instinctive self-medication through adsorptive detoxification.

It’s kind of cool how evolution has shaped certain animals to seek out natural solutions for chemical burdens in their diets; and in this case, charcoal acts as a binding agent for plant toxins. Today, this ecological phenomenon is being studied particularly in the field of livestock nutrition and climate mitigation.

A recent review by Ayeneshet & Temesgen (2025), drawing from over 100 studies, provides a comprehensive evaluation of biochar’s effects on livestock - 

• Feed Efficiency: Biochar inclusion (0.5 -3% of dry matter intake) improves nutrient absorption and feed conversion ratios, thanks to its high surface area and porosity.
  
  

• Methane Mitigation: Enteric methane production in ruminants was reduced by 30 to 40%.
  
  

• Microbiota Modulation: Studies observed significant reductions in Salmonella and coliform bacteria, and increased populations of beneficial microbes such as lactobacilli and cellulolytic bacteria.
  
  

• Performance Gains: Consistent body weight improvements were reported across cattle, pigs, poultry, goats, sheep, and even fish, highlighting broad applicability right there.

That being said, the review also cautions against uncritical adoption: biochar’s strong adsorptive properties could potentially bind not only toxins but also essential nutrients or veterinary pharmaceuticals, especially if not carefully managed.

However, this also presents a parallel opportunity - Zoo Animals. 

The behaviour of colobus monkeys raises a logical and fascinating question: Could biochar have a role in the nutrition and health of captive wildlife, particularly herbivores or omnivores with plant-rich diets?

In zoos and wildlife sanctuaries, many species are prone to digestive sensitivity, micronutrient imbalances, or limited behavioural enrichment. Incorporating biochar, if done safely and species-appropriately, could potentially support gut health, simulate wild foraging behaviour, and enhance welfare outcomes.

Here is a quick comparison - 

What colobus monkeys practice by instinct, we are now beginning to explore through empirical research and controlled trials. As biochar enters the mainstream of livestock production, it may also hold untapped value for veterinary nutrition, zoological care, and more.