> Everything from desire for friendship and love to desire
> for social status and achievement work pretty much
> EXACTLY the same
Which is why behavioural biologists don't even go down that path of "humanizing" animals - all they do is link certain behaviour to certain actions (famous example: anal-sniffing as sexual behaviour in guinea-pigs or dogs). Looking at animals through the "human glass" can lead to some insights, but can certainly lead to terribly wrong results, too:
It's like overfitting a statistical model, you'll get noise where you expect results.
As for emotions, that's a harder thing to prove. Dolphins are intelligent enough they should be classified as sentient non-human persons according to more progressive scientists. They have the richest range of emotions we've seen outside of chimpanzees, and to be honest, chimpanzees are so very nearly human it's quite amazing. They don't seem to lack any faculties that humans have, but some of their emotions are just less pronounced or developed.
Sometimes it seems the only reason that chimpanzees aren't affected more emotionally is that they don't understand the implications of what's happening. It's just ignorance more than a lack of emotion.
What might exist in the way of emotions humans don't have is things that are bio-chemical. Nature has a way of "rewarding" behaviors that are productive with a positive feeling. Do cuttlefish feel something other than love when doing their dances? What does an octopus, which has a nervous system entirely unlike a mammal or fish, feel when going about their day?
I don't really like to hear scientists described as progressive or non-progressive. I would prefer to hear that they are more or less sceptical.
Humans also possess this ability, althought it's limited and weak.
Our Burmese cats actually do seem to be a bit guilty after they do something bad, also they are very social. Having said that, Burmese cats do have a reputation for being amongst the most dog-like of cat breeds.
Even rats have empathy as proven in an experiment: http://www.wired.com/wiredscience/2011/12/rat-empathy/
We're about 80% the same as animals when it comes down to it. The difference is important, absolutely, but not as significant as you'd think.