No, bone marrow is not only in humans.
Bone marrow, the spongy tissue found inside bones responsible for producing blood cells (hematopoiesis), is present in a wide range of animals, specifically birds and mammals. While the composition and exact location of bone marrow may vary between species, its fundamental function remains consistent: generating new blood cells.
Bone Marrow in Different Species
-
Mammals: Like humans, other mammals such as dogs, cats, cows, and mice have bone marrow located primarily in their ribs, vertebrae, sternum, and pelvic bones. This is their primary site for blood cell production.
-
Birds: Birds also possess bone marrow, serving the same role as in mammals. The location of active bone marrow in birds tends to be concentrated in the femur, humerus, and pelvis.
-
Other Vertebrates: While bone marrow as defined above is characteristic of birds and mammals, other vertebrates have hematopoiesis occurring in different locations. Fish, amphibians, and reptiles typically produce blood cells in organs such as the kidney and spleen. These organs serve an analogous function but lack the specialized marrow found in birds and mammals.
In summary, bone marrow is a key characteristic of avian and mammalian species, essential for blood cell production. Although hematopoiesis occurs in other vertebrates, they lack the specific marrow structure found in birds and mammals.
