The altered presence of tiny fragments of neuronal genes, called microexons, causes hyperarousal in zebrafish. This is the main conclusion of an international study led by the Pompeu Fabra University (UPF) and the Centre for Genomic Regulation (CRG). An abnormal pattern of neural microexon presence leads to a hyperarousal state characterized by heightened neural activity and insomnia, commonly associated with stress but also in neurodevelopmental disorders. Arousal regulation is highly conserved in evolution. Therefore, this finding could help understand the mechanism underlying some human neurodevelopmental disorders, such as autism and schizophrenia, conditions associated with microexon mutations. 

Arabian Sea humpback whales have, at some point during their evolutionary history, adapted to living hyper-locally within the confines of the Arabian Sea. Now, researchers monitored their dives using satellite tags which allowed them to track their movement across the Arabian Sea. The results showed most whales are homebodies – moving within a narrow latitudinal band spanning just a few hundred kilometers. Just one whale broke the pattern and travelled across the Arabian Sea. This is the first direct evidence of a long-distance journey made by an Arabian Sea humpback whale. The team said better understanding of these whales’ movement could provide important insights for the endangered species’ conservation.

For a long time, scientists have thought that four-legged land animals (tetrapods) evolved from amphibian-like creatures that grew up from tadpoles. But scientists have now found fossilized baby early tetrapods, which skipped the tadpole metamorphosis scientists had expected to see. The finding means that the first land-dwelling vertebrates were less like modern amphibians than had previously been thought— upending scientists’ understanding of how animals conquered the land.