Aphids

Eggs overwinter--first summer generation winged (fundatrices)- Parthenogenetic fundatrices lay eggs for first generation of wingless parthenogenetic summer aphids--can be several parthenogenetic wingless generations--in fall alate males are produced, which mate with wingless females, and overwintering eggs are produced.

2. Two host plant life cycles (Example: bird cherry-oat aphid)

Eggs overwinter and hatch on cherries--first summer generation winged, parthenogenetic--second and third summer generations contain winged individuals which migrate to grasses--several generations on grasses-alate males and females appear on grasses in fall--alate females migrate to cherries, produce a wingless generation which mates with males--eggs overwinter

Reference: Dixon, A. F. G. 1973. The biology of aphids. Edward Arnold: London.

3. Aphid soldiers

In some aphid species a curious outcome of living in clones (parthenogenetic offspring of a single mother) is that some of the aphids become soldiers. They are stouter bodied and capable of defending the clone from attack. Aphid soldiers have evolved a number of times in the Hormaphididae and Pemphigidae.

Reference: Stern, D. L. 1994. A phylogenetic analysis of soldier evolution in the aphid family Hormaphididae. Proc. R. Soc. Lond. B. 256:203-209.

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