Anteaters are four distinctive mammal species belonging to the order Pilosa, which they share with sloths. The question of whether these insectivorous animals are nocturnal does not have a simple answer. Anteaters exhibit flexible activity patterns that are subject to immediate environmental conditions. Understanding their daily cycles requires looking past a single time of day and considering the specific species and their local surroundings.
Activity Varies by Species and Climate
The activity cycle of anteaters is best described as cathemeral, meaning their periods of activity are scattered throughout both the day and the night. This flexible pattern is primarily a behavioral adaptation to regulate their body temperature and avoid predators. Anteaters, particularly the large Giant Anteater, have a low metabolic rate compared to other mammals of similar size, which makes them sensitive to temperature extremes.
In regions experiencing high temperatures, the animals often become strictly nocturnal to avoid overheating during the hottest part of the day. They retire to cooler, shaded areas to rest. Conversely, in cooler climates or during colder seasons, they may shift their activity to be more diurnal, sometimes basking in the sun to warm up.
The presence of humans and large predators also strongly influences when an anteater chooses to be active. In areas with high human activity or significant predator populations, such as jaguars, anteaters tend to become more nocturnal. This shift minimizes encounters with potential threats, allowing them to thrive across diverse habitats.
The Four Main Types of Anteaters
The four extant species of anteaters differ significantly in size, habitat, and general activity tendencies. The largest species is the Giant Anteater (Myrmecophaga tridactyla), which is almost exclusively terrestrial and exhibits the most flexible, cathemeral schedule. Their immense size necessitates this flexibility to find sufficient food and manage their body heat.
The Northern Tamandua (Tamandua mexicana) and the Southern Tamandua (Tamandua tetradactyla) are medium-sized, semi-arboreal species. Tamanduas are scansorial, meaning they are adept at climbing trees but also spend significant time on the ground. They are often described as being nocturnal or crepuscular, meaning most active during twilight hours, though they are frequently seen during the day.
The smallest species is the Silky Anteater (Cyclopes didactylus), a tiny animal weighing only about 250 grams. Silky Anteaters are almost entirely arboreal, living high in the forest canopy. They have the strongest tendency toward nocturnality among the four species, which helps them hide from predators and forage safely.
Specialized Foraging Behavior
All anteaters share a specialized method of feeding, known as myrmecophagy, which focuses on consuming ants and termites. Their anatomy is uniquely adapted for this insect-based diet. They possess a long, cylindrical snout and a sticky, vermiform (worm-like) tongue that can extend up to two feet in the Giant Anteater.
Powerful forelimbs tipped with large, strong claws allow them to rip open the hard outer walls of ant and termite mounds. Once the nest is breached, the tongue flicks in and out rapidly, often up to 150 times per minute, gathering insects coated in sticky saliva.
Anteaters feed for only short periods, typically less than a minute at any single nest, rather than destroying the entire colony. This rapid feeding is a strategy to avoid the aggressive chemical and physical defenses of the insect soldiers. By visiting up to 200 nests in a single day, an anteater can consume over 30,000 insects to meet its nutritional requirements.