英语怎么说恐龙灭绝的真正原因

The true cause of the dinosaur extinction, as widely accepted by the scientific community, was the catastrophic impact event approximately 66 million years ago. This event involved a massive asteroid, estimated to be about 10 kilometers in diameter, colliding with the Earth. The impact, which occurred near the present-day Yucatán Peninsula in Mexico, generated an enormous amount of energy, equivalent to billions of nuclear bombs.

The immediate effects of the impact were devastating. A massive shockwave propagated through the atmosphere and the ground, causing widespread destruction. The impact also ejected vast quantities of debris, including dust, soot, and rock fragments, into the atmosphere. This debris cloud circled the globe, blocking sunlight for an extended period.

The prolonged lack of sunlight had severe consequences for photosynthesis, the process by which plants convert light into energy. Plants, which form the base of most food chains, began to die off en masse. This led to a cascading collapse of the food web, as herbivores lost their food source and subsequently became extinct. Predators that relied on these herbivores also faced starvation and extinction.

In addition to the impact, other factors may have contributed to the extinction event. These include massive volcanic activity, which could have released vast amounts of greenhouse gases and particulate matter into the atmosphere, further exacerbating climate change and environmental stress.

The combined effects of the impact, the subsequent atmospheric changes, and ongoing volcanic activity created a hostile environment that most species, including the non-avian dinosaurs, could not survive. Over time, the Earth's climate gradually recovered, and life began to re-establish itself, eventually leading to the evolution of mammals and, much later, humans. The extinction of the dinosaurs remains one of the most significant events in Earth's history, reshaping the course of life on our planet.