instruction:
Generate an overlapping word between the given two sentences. When you find the overlapping words, they don't have to match exactly, e.g., "survival" and "survive" are valid overlapping words. Little words like "the" or "of" don't count! You must generate significant words which are not the stop words.
question:
Sentence1: Adaptation traits contribute to individual fitness and to the evolution of animal genetic resources. 
Sentence2: Behaviors can improve the evolution of animal genetic resources.
answer:
animal


question:
Sentence1: Echinoderms lack respiratory and excretory systems. 
Sentence2: echinoids lack a respiratory system.
answer:
respiratory


question:
Sentence1: Running water is better able to dissolve oxygen and nutrients than standing water. 
Sentence2: Rivers can better dissolve oxygen and nutrients than lakes.
answer:

dissolve