Canis lupus furlongi

Canis lupus furlongi is not morphologically distinct from modern wolf populations, only differing in having a broader femur bone and a longer tibial tuberosity – the insertion for the quadriceps and hamstring muscles – indicating that they had comparatively more powerful leg muscles for a fast take-off before a chase.^[7] This wolf subspecies is similar in size to the Beringian wolf, whose remains have been found at Alaska, Yukon, and northern British Columbia.^[8]

The last glacial period, commonly referred to as the "Ice Age", spanned 125,000–14,500 YBP and was the most recent glacial period within the current ice age, which occurred during the last years of the Pleistocene era.^[9][10] The Ice Age reached its peak during the Last Glacial Maximum, when ice sheets began advancing from 33,000 YBP and reached their maximum limits 26,500 YBP. Deglaciation commenced in the Northern Hemisphere approximately 19,000 YBP and in Antarctica approximately 14,500 YBP, which is consistent with evidence that glacial meltwater was the primary source for an abrupt rise in sea level 14,500 YBP.^[11] Access into northern North America was blocked by the Wisconsin glaciation. The fossil evidence from the Americas points to the extinction mainly of large animals, termed Pleistocene megafauna, near the end of the last glaciation.^[12]

Remains of Furlong's wolf are rare when compared to the dire wolf, hinting that Furlong's wolf didn't thrive in environments with dire wolves. This suggests the dire wolf was the dominant wolf in California during the Pleistocene epoch.^[13]