Dinosaurs that adapted to marine environments, such as plesiosaurs and ichthyosaurs, were not true dinosaurs but rather marine reptiles. They faced significant challenges, including competition with other marine predators, changes in sea levels, and climate shifts during the late Cretaceous period. The mass extinction event around 66 million years ago, likely caused by an asteroid impact and volcanic activity, drastically altered ecosystems, leading to the extinction of many marine species, including these adapted reptiles. Ultimately, their specialized adaptations may have limited their ability to survive the rapid environmental changes.
No dinosaurs lived in the sea. There were other reptiles that adopted a marine life, but those weren't dinosaurs.
When the dinosaurs lived there were sea monsters but they were called marine reptiles and were not dinosaurs.
A marine mammal is an animal that lives in the ocean and breathes air, like whales, dolphins, seals, and manatees. These animals have adapted to life in the water and often have special characteristics to help them survive in the marine environment.
Although some dinosaurs were probably able to swim there were no true marine dinosaurs. There were marine reptiles that some colloquially refer to as dinosaurs, but these were actually a separate group called plesiosaurs. Another group that lived in the age of the dinosaurs were the flying reptiles pterosaurs. These are also incorrectly referred to as dinosaurs by many, but they were themselves a separate but closely related group. However, fossil evidence shows that birds are descended from small carnivorous dinosaurs and can in fact be classified as modern dinosaurs.
Plesiosaurs were not dinosaurs. They were a clade of marine reptiles that lived at the same time as the dinosaurs.
Underwater dinosaurs, or more accurately, marine reptiles like plesiosaurs and ichthyosaurs, primarily fed on a diet of fish, squid, and other marine organisms. Their sharp teeth and streamlined bodies were well-adapted for catching and consuming prey in the ocean. Some larger species may have also hunted smaller marine reptiles or scavenged carcasses. Overall, their diet varied based on their size, habitat, and available prey.
The structures that make the perch adapted for living in water are the gills, fins, and streamline-shaped body. All designed to survive in different waters (marine and fresh water).
There were no ocean dwelling dinosaurs. Large marine reptiles that are often thought of as dinosaurs include plesiosaurs, pliosaurs, mosasaurs, and icthyosaurs.
Dinosaurs never lived underwater. There were marine reptiles that are sometimes inaccurately called dinosaurs; these include icthyosaurs, mosasaurs, plesiosaurs, and pliosaurs. All of these are extinct. There are a few marine reptiles alive today, though. These are sea turtles, sea snakes, and the semi-aquatic marine iguana.
Elasmosaurus was a giant plesiosaur, which were a group of marine reptiles. However, nono of these marine reptiles were dinosaurs.
The amount of sunlight in the marine biome varies depending on the depth of the water. In shallow waters, sunlight can penetrate and support photosynthesis for marine plants and algae. In deeper waters, sunlight is limited and organisms have adapted to survive in low light conditions or with alternative energy sources like chemosynthesis.
They include Ankylosaurs (the armored dinosaurs), Mosasaurs, and Plesiosaurs (both marine reptilian groups).