Question: What do you think marked this tree near Crater Lake: a bear or a human?
Answer: A bear! Bear claws are like our finger nails, but much longer, harder, and sharper. Claws help bears mark or climb trees, tear apart rotten logs to eat ants, and dig in the ground for rodents and edible roots.
Grizzly bears have claws much longer than black bears, so they are better diggers, but black bears are better tree climbers with their shorter claws.
Grizzly bear claws
Black bear claws
To learn more about the difference between grizzly bears and black bears, check out http://fwp.mt.gov/recreation/safety/wildlife/bears/bearId.html