Core Insights - A significant change is occurring in the Antarctic marine food web, with a decline in diatoms, which may impact the entire Antarctic ecosystem and its ability to regulate climate [1][2] Group 1: Research Findings - An international team analyzed 14,824 phytoplankton samples collected from the Southern Ocean between 1997 and 2023, revealing a decrease in diatoms, which are being replaced by dinoflagellates and cryptophytes [1] - Diatoms are a primary food source for krill, which in turn are essential for penguins, seals, and baleen whales, indicating that the decline of diatoms could disrupt the food chain [1] - The study published in the journal Nature Climate Change highlights that the surface water in the observed areas has seen a decrease in iron content and an increase in temperature, which may be driving the changes in phytoplankton populations [1] Group 2: Ecological Implications - Diatoms have a heavier silica structure that allows them to sink quickly after death, effectively sequestering carbon in the deep sea, whereas dinoflagellates and cryptophytes have a lower carbon sequestration capability [1] - The research emphasizes the need for further studies on the interaction between climate change and the Antarctic ecosystem, as these changes may exacerbate climate change through feedback mechanisms [2]