What type of information are used to make a cladogram

you need to have characteristics. Use a diagonal line and draw straight lines from it, at the top of the lines add the organisms like tuna, salamander. You would put in between the two lines what makes tuna and salamanders diffeerent like 4 legs. Look up cladograms and there should be many pictures. What you realy need to know is the characterist applies to all the animals above in a caldogram.

Explanation:

any abiotic or biotic factor in an ecosystem that causes a population's size to slow or decrease is a limiting factor.