Unfortunately, about 90% of what Koko could or did do was a hoax. I don't know specifically if this particular graphic is included in that or not, but when I hear Koko, I am immediately super-skeptical.
Which is kind of sad, because it masked a lot of really amazing things apes actually can do.
If animals had souls then the big Gee Whiz would bring them to heaven too. But nope. Pet-hater Jesus is leaving all our cats and dogs behind at the rapture. If you love your kittehs or your puppies you should definitely seek out the services of a secular humanist to take care of your pal after the rapture.
Which is kind of sad, because it masked a lot of really amazing things apes actually can do.