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The Komodo dragon, Varanus komodoensis, is a large predatory lizard native to Indonesian islands. It takes animal prey and also scavenges. The scientific name identifies the species, while the familiar name does not denote a separate evolutionary group from other lizards.^[ref]

Its reproduction provides a striking example of facultative parthenogenesis: production of offspring without fertilization can occur in a species that also reproduces sexually. A 2006 study examined offspring from two females isolated from males at separate institutions. Microsatellite genotypes and reproductive histories supported maternal-only inheritance; one female later also produced sexually conceived offspring.^[ref]

Genetic comparison matters because the absence of a male at laying does not alone exclude earlier mating or stored sperm. As a simplified example, a mother carrying alleles $A$ and $B$ at a locus might produce a parthenogenetic offspring carrying two copies of $A$. That offspring contains only a maternal allele but is not an identical genetic copy of its mother. Evidence from several loci is more informative than this single-locus illustration.

The observation therefore distinguishes parthenogenesis from simple cloning and shows that reproductive mode can vary within a species. It does not establish that all isolated females must reproduce this way or that every form of animal parthenogenesis has the same genetic mechanism.

Phillip C. Watts is a researcher in population genetics and conservation genetics, studying relationships between genetic variation and the environments experienced by wildlife. His research uses genomics to investigate biological responses to environmental change.^[ref]

In a 2006 study, Phillip C. Watts and collaborators used DNA profiling to investigate offspring produced by female Komodo dragons isolated from males at two institutions. The genetic evidence supported parthenogenesis. One female later reproduced sexually, showing that a single individual could use both reproductive modes.^[ref]

The example shows why an observation of an apparently unmated female laying viable eggs needs genetic evidence. Offspring genotypes can test explanations that husbandry records alone cannot settle. Here the combination of isolation history and inherited markers supported reproductive flexibility in a vertebrate, rather than establishing a rule that every isolated female will reproduce this way.