Failed to understand " carry out clearly ranks it". What does it mean?

Context:

I completely agree with the above comment. Of course an animal of a certain species will be better suited to carry out the functions of that species than an animal of a different species. This goes without saying, as this is how evolution has engineered the animal kingdom. If we are to proceed by your standards, every animal species on earth will be infinitely intelligent, relative to itself. Comparing an animal's intelligence to another's does not go to show how "humble" we are or "how little we know". It is used to draw correlations between the two. The universal abilities to reason, theorize, defend, acclimate all go to show intelligence and the evolutionary strength of that species. The complexity of the functions a species is able to carry out clearly ranks it above or below another in terms of intelligence. I suggest that next time you are asked about the intelligence of camels (as you 'often' are), you skip arbitrarily quoting a spiritual leader and instead, pass the inquiry on to someone who is actually well-versed in such research and can hopefully provide an adequate, objective answer.

More:
http://cameland.blogspot.com/2007/10/intelligence-in-camels.html