All articles tagged with #population study
A large Norwegian population study found that the prevalence of Alzheimer’s disease neuropathological changes increases with age, reaching 65.2% in those over 90, with 10% of those over 70 having preclinical AD, highlighting the importance of blood-based biomarkers for large-scale assessment and potential treatment eligibility.
A Swedish study found that the rise in autism and ADHD diagnoses over recent years is not matched by an increase in symptoms among 18-year-olds, suggesting that factors like increased awareness and diagnostic criteria changes, rather than an actual rise in symptoms, are driving the trend.
A new study suggests that a group of killer whales spotted off the coast of California and Oregon over two decades may represent a previously uncategorized population of orcas. These orcas exhibit unique behavior and ecology, including deep-sea habitat preferences and distinctive scarring from encounters with cookiecutter sharks. The study's findings shed light on the presence of a distinct oceanic population of killer whales and highlight the importance of further research and observation to understand their behavior and ecological significance.
Researchers from the UBC Institute for the Oceans and Fisheries suggest that a group of 49 orcas observed hunting marine mammals in the open ocean off California and Oregon could represent a new population of killer whales. These orcas, distinguishable by cookie-cutter shark bite scars and physical differences from known ecotypes, have been encountered multiple times from 1997 to 2021. The researchers hope to gather more data, including acoustic and genetic information, to further investigate the unique characteristics of this potential new population.