QUOTE (Running Wild page 24)
Critter Attributes
Critters are measured on the same scale as metahumans, which means they can be perceived as amazingly fragile or vastly strong in comparison. Critters with a Body attribute of 0 are unable to soak damage and are immediately destroyed if successfully struck. (Note that many insects with a Body of 0 act as Swarms. See Swarms, p. 25, for details.) Likewise, critters with a Strength of 0 are able to move their own body mass but do not approach the strength of even the weakest infant. If a critter has an attribute of 0, it does not add dice for the linked attribute in any tests or skills related to that attribute.
Apart from the critters with Body 0, they all hav CM just like metahumans.