Mammuthus exilis, pygmy mammoth, was a dwarfed descendant of full-sized mammoths, possibly Mammuthus columbi , the Columbian mammoth. M. exilis lived on the northern Channel Islands of California of Santa Cruz Island, Santa Rosa Island, and San Miguel Island. The ancestral mammoth probably swam across the Santa Barbara Channel about 20,000 years BP. At the time, these three islands, along with Anacapa Island formed a single land mass known as Santa Rosae.

M. exilis stood about 120-240cm (4-8 feet) high at the shoulder.

References

• Channel Island Park update on pygmy mammoth
• Agenbroad, L. D. Channel Islands (USA) pygmy mammoths (Mammuthus exilis) compared and contrasted with M. columbi, their continental ancestral stock.