Microbiology
Thermophiles (Pyrococcus furiosus) and Psychrophiles (Pseudomonas fluorescens)
Xerophytes (Carnegiea gigantea) and Hydrophytes (Nymphaea odorata)
Detritivores (Lumbricus terrestris) and Decomposers (Agaricus bisporus)
Mesophile (Escherichia coli) and Neutrophile (Homo sapiens)