A recent study has found that around 5% of common Australian wild birds, including kookaburras and lorikeets, may have undergone “sex reversal”, where their genetic sex does not match their reproductive organs. The research tested 480 birds across five species and found 24 instances of mismatched DNA and physical characteristics.
The study suggests that sex reversal is more common in wild birds than previously thought, raising concerns about the impact of chemicals that can disrupt hormones in animals. Researchers believe that contact with environmental chemicals could be to blame for the phenomenon, which has also been observed in other animal species such as molluscs, fish, and reptiles.
The study’s findings have sparked debate among experts, with some suggesting that sex reversal could skew data on bird populations and lead to reduced reproductive success. Others believe that the prevalence of EDCs in the environment may be contributing to the issue, particularly in birds where the default sex is female.
While more research is needed to determine the causes of sex reversal in wild birds, the study’s findings have significant implications for our understanding of animal health and the impact of environmental pollutants.
Source: https://www.theguardian.com/environment/2025/aug/14/sex-reversal-australian-birds-kookaburras-lorikeets