Throughout the history of our planet, few creatures have managed to capture human fascination like dinosaurs. The colossal animals that once inhabited earth have been filling our screens, books and even trunks with toys ever since we remembered them.However, after living a lifetime with the memories of dinosaurs, do we know them as well as we think?
Then, in Animal Expert, let’s delve into one of the great mysteries of evolution: how did dinosaurs disappear?
- We call dinosaurs the reptiles included in the superorder Dinosauria.
- From Greek deinos.
- Which means “terrible”.
- And sauros.
- Which translates as “lizard”.
- Although we should not confuse dinosaurs with lizards because they belong to two different categories of reptiles.
Fossil records indicate that dinosaurs led the Mesozoic era, known as the “age of large reptiles”.The oldest dinosaur fossil found to date (a specimen of the species Nyasasaurus parringtoni) is approximately 243 million years old and therefore belongs to the Middle Triassic period.At that time, today’s continents were united forming the great mass of land known as Pangeia.The fact that the continents were not yet separated by the sea at the time allowed the dinosaurs to spread rapidly to the Earth’s surface.of Pangeia in continental blocks of Laursia and Gondwana in the early Jurassic stimulated the diversification of dinosaurs, resulting in many different species.
This diversification has favored the appearance of dinosaurs with a wide variety of characteristics, traditionally classified in two orders, according to the orientation of their basin:
Within these categories are animals of very variable wingspan, from compsognatus, the smallest dinosaur discovered to date, close to the size of a chicken, to the fearsome Brachiossaurus, which reached an impressive height of 12 meters.
Dinosaurs also had the most diverse forms of feeding, although it is difficult to confirm with certainty the specific diet of each species, they are considered to be mainly herbivores, although there are also several carnivorous dinosaurs, some of which were fed on other dinosaurs, such as the famous Tyrannosaurus rex.Some species, such as Baryonyx, also feed on fish.There were dinosaurs with an omnivorous diet, and many of them did not refuse to eat carrion.For more details, don’t miss the article about the types of dinosaurs that existed.”
Although this diversity of life forms facilitated the colonization of the entire planet in the Mesozoic era, the dinosaur empire ended with the last Cretaceous strikes 66 million years ago.
The extinction of dinosaurs is, for paleontology, a puzzle of a thousand pieces and difficult to solve, was it caused by a single determining factor or was it the result of the disastrous combination of several events ? , was it a sudden and abrupt process or a gradual process over time?
The main obstacle to explaining this mysterious phenomenon is the incompetitude of the fossil record: not all specimens are preserved in the terrestrial substrate, which gives an imperfect idea of the reality of the time, but thanks to the continuous technological progress new data have been obtained.revealed in recent decades, allowing us to offer slightly clearer answers to the question of how the dinosaurs disappeared.
Radioisotope dating saw the extinction of dinosaurs about 66 million years ago, so when did the dinosaurs disappear?At the end of the Cretaceous, our planet at the time was a place with an unstable environment, with radical changes in temperature and sea level, these changing weather conditions could lead to the loss of some key species in the ecosystems of the time, altering the food chains of the remaining individuals.
The same thing happened when the volcanic eruptions of the Deccan traps began in India, releasing sulfur and carbon in large quantities and promoting global warming and acid rain.
As if that were not enough, soon came the main suspect of the extinction of the dinosaurs: 66 million years ago, the Earth was visited by an asteroid about 10 km in diameter, which collided with the now called Yucatan Peninsula in Mexico and left the Chicxulub crater, which stretches along 180 kilometers, as a souvenir.
But this huge gap on the Earth’s surface was not the only thing the meteor brought: the sudden collision caused a seismic disaster that shook the Earth; In addition, the impact zone was rich in sulfates and carbonates, which were released into the atmosphere producing acid rain and temporarily destroying the ozone layer.It is also thought that dust lifted by the cataclysm may have intertposed a layer of darkness between the Sun and Earth, reducing the rate of photosynthesis and damaging plant species.have led to the ruin of herbivorous dinosaurs, which would take the carnivores with them to the precipice of extinction.Thus, due to reliefs and climate change, dinosaurs were unable to feed and began to die.
The information discovered so far has given rise to a multitude of theories about the possible cause of the extinction of dinosaurs, as you saw in the previous section Some people give more importance to the impact of the meteorite as a brutal cause of the extinction of dinosaurs; others believe that environmental fluctuations and intense volcanic activity at the time stimulated its gradual disappearance. Also noteworthy are the proponents of a hybrid hypothesis: this theory suggests that climatic conditions and rabid volcanism have fueled the slow decline of dinosaur populations, which were already in a vulnerable situation.position when the meteorite struck grace.
So what caused the extinction of the dinosaurs? While we cannot say for sure, the hybrid hypothesis is the most supported theory, as it argues that several factors led to the extinction of dinosaurs during the late Cretaceous period.
Although the disaster that caused the extinction of dinosaurs had a global impact, some animal species managed to survive and develop after the cataclysm, as is the case with certain groups of small mammals, such as Kimbetopsalis simmonsae, a species whose individuals are beavers.Like herbivores, why did dinosaurs disappear and not mammals?This is because, being smaller, they needed less food and could better adapt to the new environment.
Sobreviveram também certos insetos, caranguejos-ferradura e os ancestrais arcaicos dos atuais crocodilos, tartarugas marinhas e tubarões. Além disso, os amantes de dinossauros que estão aflitos pensando que nunca poderão ver um iguanodonte ou pterodátilo devem se lembrar que essas criaturas pré-históricas nunca desapareceram completamente – algumas ainda sobrevivem entre nós. De fato, é muito comum vê-las em um belo dia passeando no campo ou quando corremos pelas ruas de nossas cidades. Embora possa parecer incrível, estamos falando das aves.
During the Jurassic period, theropod dinosaurs suffered a long evolutionary process, resulting in several species of archaic birds that coexisted with the rest of the dinosaurs.When the Cretaceous hecatombe occurred, some of these primitive birds managed to survive, evolving and diversifying towards today.
Unfortunately, these modern dinosaurs are also in decline, and it is easy to identify the reason: this is the human impact.Habitat destruction, the introduction of exotic competing animals, global warming, hunting and poisoning have resulted in the disappearance of a total of 182 bird species since 1500, while about 2,000 others have been threatened.Our unconsciousness is the accelerated meteor that hovers over the planet.
They say that we are witnessing the sixth great mass extinction live and in color, if we want to avoid the disappearance of the last dinosaurs we must fight for the conservation of birds and reserve a high degree of respect and admiration for the feathered aeronauts that we encounter.Every day: the pigeons, magpies and sparrows that we are used to see, carry their fragile bones.let’s say a legacy of giants.
The impact of meteorites and volcanism has led to the generation of seismic phenomena and fires that have amplified global warming; however, subsequently the appearance of dust and ash that darkened the atmosphere and blocked the passage of the sun’s rays produced a cooling of the planet.This abrupt transition of extreme temperatures resulted in the extinction of about 75% of the species that inhabited the Earth at the time.
However, life soon reappeared in this devastated environment, the atmospheric dust layer began to disintegrate by letting light pass, mosses and ferns began to grow in the most affected areas, the least affected aquatic habitats have proliferated The rare fauna that managed to survive the disaster has multiplied, evolved and spread throughout the planet.After the fifth mass extinction that devastated Earth’s biodiversity, the world continued to revolve.
If you would like to read articles similar to, we recommend that you visit our Curiosities section of the animal world.