Sierra gooseberries (Ribes roezlii) are covered in sharp spines. Tasty and sweet, humans can barely pick the well-armored fruits without hand protection, let alone eat them. (See my 07-20-2016 article, “Sierra Gooseberries”).
Golden-mantled ground squirrels (Citellus lateralis) have no problem eating Sierra gooseberries. I watched this little rodent near Medicine Lake (Siskiyou County CA) grab a Sierra gooseberry, wrestle it off the bush and eat the prickly berry without any difficulty. I cannot pick a Sierra gooseberry without hand protection and would never consider popping one into my mouth. It was amazing that the spines had no effect on the ground squirrel.
Refer to my 11-13-2013 post “Young Golden-mantled Ground Squirrels” for more information on this cute mammal.