The Australian jack jumper ant (Myrmecia pilosula) has a diploid chromosome number of just 2 in females (males, being haploid, have just 1 chromosome) — the lowest confirmed chromosome number of any animal, making its single chromosome pair a model system for studying chromosome mechanics and meiosis.
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The Australian jack jumper ant (Myrmecia pilosula) has a diploid chromosome number of just 2 in females (males, being haploid, have just 1 chromosome) — the lowest confirmed chromosome number of any animal, making its single chromosome pair a model system for studying chromosome mechanics and meiosis.
The lowest diploid chromosome number confirmed by karyotyping in a sexually reproducing animal species, as documented in cytogenetic literature.
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Limits Registry. LR-SMALLEST-CHROMOSOME-COUNT-ANIMAL. Lowest chromosome number recorded in an animal species. 2026.