Whales and Dolphins in the World of Humans: How Noise, Ships, and Plastic Change Their EvolutionWhen we talk about climate change, we often think about temperature and sea level. But for whales and dolphins, the main challenge of the 21st century is not just heat, but human with all its technology. The noise from ships, plastic in their stomachs, fishing nets, sonars from military ships, tourist boats, and even light in night ports all create a new environment to which marine mammals have to adapt. And they do adapt. Their songs, routes, hunting methods, and social behavior change. But will they evolve quickly enough to avoid extinction? This question concerns scientists and requires an answer today.Noise Pollution: When the Ocean Stops Being QuietFor whales and dolphins, sound is a primary tool for survival. They use echolocation to find food, communicate with conspecifics, navigate space, and avoid dangers. But every year, the ocean becomes louder. The noise from shipping, seismic research, wind farm construction, and military sonar mutes their signals.Research shows that some whale populations are changing the frequency of their songs to \"outcry\" the noise. This requires additional energy expenditure and may affect their ability to reproduce. Moreover, noise causes stress, increases cortisol levels, and may even lead to temporary or permanent hearing loss. In particularly noisy areas, whales simply leave their usual habitats, disrupting their migration routes and food search.Physical Obstacles: Ships, Nets, and TouristsWhales and dolphins increasingly encounter the physical environment created by humans. Thousands of ships cross oceanic routes, and collisions with them are one of the main causes of death for large whales. Moreover, fishing nets become a deadly trap: entangled, animals die from suffocation or starvation. Plastic waste, which they often mistake for food, clogs their stomachs and leads to a painful death.Tourist boats that come close to whales for ...
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