Australopithecus is a genus, it has no plural. You could speak of the Australopithecines though, which are the extinct human-like primates of the genus.
The plural form of rat is 'rats'.
The plural of zoo is zoos. The plural possessive form of zoos is zoos'.
The plural possessive form of lion is lions'.
The plural is fossae.
The plural of squirrel is squirrels.
The plural form of Australopithecus is Australopithecines.
The species from which H. sapiens evolved was probably some form of Australopithecus, possibly Australopithecus afarensis.
An australopith is an extinct form of hominid primate of the genus Australopithecus.
Bridges is the plural form of bridge.
"Beliefs" does not have a plural form, as it is already plural. Beliefs is the plural form of belief.
There is no plural form for the word, countries. This word itself is a plural.
"Groceries" is the plural form of "grocery."
The plural form of "meter" is "meters."
The plural form for the noun sergeant is sergeants; the plural possessive form is sergeants'.
It has no plural form.
The plural form of rung is rungs.
The plural form of mouth is mouths. The plural form of month is months. The Mounth is a range of hills in Scotland and does not have a plural form.