The channels are formed by concentric layers called lamellae, which are approximately 50 μm in diameter.

This unique arrangement is conducive to mineral salt deposits and storage which gives bone tissue its strength.

[1] Haversian canals are contained within osteons, which are typically arranged along the long axis of the bone in parallel to the surface.

The canals and the surrounding lamellae (8-15) form the functional unit, called a Haversian system, or osteon.

Even though some authors tried to identify a correlation between endothermy and secondary Haversian reconstruction, this feature is absent in many living mammals (e.g. monotremes, Talpa, flying foxes, Herpestes, Dasypus) and birds (Aratinga, Morococcyx, Nyctidromus, Momotus, Chloroceryle) while others possess only scattered Haversian systems (e.g. artiodactyls, Didelphis, Anas, Gallus, turkey, helmeted guineafowl).