Moa Leg Bone Replica A Tibiotarsus

Description

Moa Leg Bone Replica A Tibiotarsus (Dinornis novaezealandiae) Information

Moa leg bone replica A tibiotarsus measures 31.3 in. The Dinornis novaezealandiae bone is museum-quality polyurethane resin cast. 1: 1. Made in USA. New Zealand South Island Pleistocene.

The tibiotarsus is the largest bone in a bird’s lower leg, positioned between the femur (thigh) and the tarsometatarsus (lower leg). In common terms, such as in poultry, this bone is known as the “drumstick.”

Anatomy and Structure

The tibiotarsus is a composite bone. It is formed by the fusion of the tibia with the proximal tarsals (the upper bones of the ankle).

A key feature of this bone is the fibula, which in birds is typically reduced to a thin, splint-like bone. It remains attached to the lateral side of the tibiotarsus and usually extends about two-thirds of its length.

Functional Morphology

Based on morphological data from the CABI Digital Library, several specific structures define the tibiotarsus:

• Cnemial Crest: Located at the proximal end (near the knee), this bony protrusion provides a large surface area for the attachment of major leg muscles.
• Condyles: The distal end (near the ankle) features lateral and medial condyles. these articulate with the tarsometatarsus to form the functional ankle joint.
• Intercondylar Fossa: This is the deep groove between the condyles that helps stabilize the joint during movement.

Evolutionary Significance

While the tibiotarsus is a standard feature of all modern birds, fossil records show that similar fused structures appeared in certain dinosaur groups, such as the Heterodontosauridae. This indicates that the fusion of the ankle and shin bones was an evolutionary adaptation for efficient bipedal walking and running.

Application to Moa Studies

In extinct flightless birds like the moa (Dinornis), the tibiotarsus was exceptionally thick and heavy to support their massive body weight. Specimens from the South Island Giant Moa can reach lengths of over 31 inches, representing one of the largest avian leg bones ever recorded.

Scientific Classification

• Kingdom: Animalia
• Phylum: Chordata
• Class: Aves
• Infraclass: Palaeognathae
• Clade: Notopalaeognathae
• Clade: Dinocrypturi
• Order: †Dinornithiformes Bonaparte, 1853
• Type species: †Dinornis novaezealandiae Owen, 1843

Temporal range:

• Miocene – Holocene, 17–0.0006 Ma

Examine the massive hind limb morphology of this extinct ratite with a 1:1 scale museum-quality tibiotarsus cast. This replica highlights the exceptionally thick cortical bone and robust cnemial crest essential for dinornithiform osteology studies. It serves as a vital comparative tool alongside our dodo skeleton, southern cassowary skull, and ostrich skull replica. This Dinornis novaezealandiae specimen provides the precise anatomical detail required by professional biologists and paleozoology researchers. Shop for more museum-quality replicas in our bird or aves replica store.