Tiktaalik roseae is an extinct sarcopterygian (lobe-finned fish) from the late Devonian period, about 375 million years ago. It had both fish and tetrapod features, such as a flat head, robust ribcage, and limb-like fins, suggesting it was capable of supporting itself in shallow water or on land. Tiktaalik lived in a freshwater environment, playing a crucial evolutionary role as a transitional form between aquatic and terrestrial vertebrates.

Tiktaalik roseae is known from the Late Devonian period, approximately 375 million years ago. Fossils of Tiktaalik have been discovered in present-day Ellesmere Island in Nunavut, Canada, which was part of a large landmass near the equator during the Devonian.

During the Devonian, the region where Tiktaalik was found was characterized by warm, tropical climates with extensive river systems and floodplains. The environment was likely a deltaic or estuarine setting, with shallow, slow-moving waters.

Tiktaalik occupied a unique niche as a transitional species between fish and early tetrapods. It likely lived in both aquatic and semi-terrestrial environments, using its limb-like fins to navigate shallow waters and possibly venture onto land. The organism's adaptations suggest it was capable of supporting itself in waterlogged areas and along the water's edge, exploiting resources in both aquatic and terrestrial ecosystems.