Regarding animal thought, there's probably a common tendency, like Temple Grandin's below, to consider them utterly dependent upon wholesale visual, audible, etc., memories (not represented and symbolically condensed by language) to apply to immediate experiences for any limited reflection and understanding.
Do Animals Think Like Autistic Savants?: http://www.sciencedaily.com/releases/2008/02/080219203603.htm
"Grandin, who responds to the authors' critique in a special commentary, suggests that 'the basic disagreement between the authors and me arises from the concept of details -- specifically how details are perceived by humans, who think in language, compared with animals, who think in sensory-based data. Since animals do not have verbal language, they have to store memories as pictures, sounds, or other sensory impressions.' And sensory-based information, she says, is inherently more detailed than word-based memories. 'As a person with autism, all my thoughts are in photo-realistic pictures,' she explains. 'The main similarity between animal thought and my thought is the lack of verbal language.'"
I am very skeptical about this.
How do people propose to know what goes on inside an animal's head? By taking a very specific set of human standards, testing animals by those standards, and then extrapolating the findings?
And how does Grandin, as an autist, propose to know what non-autist thought is like?
What she says there is just a particular neuro-linguistic theory speaking.
Then there is the question of what psychological ego defense mechanisms does a famous (fame-seeking?) autist have and how do they manifest? It's not like autists would automatically be beyond ego defense mechanisms.
What if all human thought is principally the same, and the differences are only in how people explain and justify their thinking, esp. in social situations where they try to maintain a particular self-image and evoke a particular image of themselves in others?
To me, Grandin's self-descriptions spell "I'm really cool, you know" between the lines.
But let's not forget that many animals have a repertory of communication signals that can be far more complex than traditionally believed. Even wild turkeys have 25 to 30 calls consisting of items like "gobbles," "putts," "clucks," "purrs," "yelps," "cutts," "cackles," "whines," and "kee-kees" which additionally have different inflexions within those vocalizations that have their own specific meanings (as Joe Hutto mentions in the PBS "Nature" episode "My Life As A Turkey"). Certainly this by no means replaces their assumed heavy dependence on recalling stored sensory data. But animals may share more with humans in how they 'think' than, again, is commonly believed.
Or, calling upon a different neuro-linguistic theory, we can conceive of the whole matter differently.
I remember reading in an old Hindu text about pigeons, and how a pigeon thinks about how to mate, raise their young, how to feed etc. And it seems evident that the text is clearly referring to pigeons, the birds, that it's not a metaphor, not a fable, and it ascribes animals the ability to think, feel and will, just as humans think, feel and will.
In the West, it has been Christianity that popularized the divide between animals and humans - the famous "animals have no souls." In some other cultures, all living beings are considered essentially the same, they just happen to be outwardly in different bodies - some as birds, some as plants, some as humans, etc..
Imagine how different our approach to neurolinguistics would be, if we had started out with ontological positions like the Hindus.