Experimental manipulations of early Drosophila embryos. II. Adult and embryonic defects resulting from the removal of blastoderm cells by pricking.

Cells were removed from three regions (anterior, mid-lateral and posterior) of Drosophila eggs at blastoderm formation, by pricking. Embryonic defects were generally correlated with the site of damage, as is also found with microcautery and with u.v. irradiation. But many structures can develop autonomously, independently of surrounding damage. Most hatching adults were normal, suggesting that there may be mechanisms which permit compensation for cell loss. Malformed or missing adult structures are those expected from the fate map obtained from studies of genetic mosaics.