Re: How many different colors of blood are there in the world ecosystem?

The color of blood differs according to the presence or absence of respiratory 
pigments and the type of pigment used by an organism.  Animals use the 
respiratory pigment hemoglobin.  Hemoglobin transports oxygen (or carbon 
dioxide) using iron, thus animals have blood that is colored red.  Many arthropods 
and some molluscs use hemocyanin which gives their blood a faint bluish color 
due to the presence of copper.  Insects on the other hand, do not use respiratory 
pigments to transport oxygen, rather they have branching tubes called trachae that 
suck in air.  Insect blood, therefore, does not have a color due to a respiratory 
pigment.  The color of insect blood, colorless, yellow, or green, likely comes from 
the pigments of food the insect eats (e.g. chlorophyll in plants).

I hope this answers your question!