Do you know Blue whale is the largest creature and bigger than dinosaurs to have resided on earth? But not a single mammal that walks on earth surpasses the size of super-dinosaurs. Talking about dinosaurs, the species that has the largest record in Amphicoelias Fragillimus having 60m & 122 metric tons weight.
In comparison to, the Savanna elephants of Africa are the modern largest and animal that clocks in 3-4m tall & five and a half tons where both are herbivores.
So now is the time to answer the questions “Why are there no animals on land that level with or surpass the size of the dinosaur?”
According to the fossil records when 65 million years ago dinosaurs disappeared, mammals hit their limit in respect of size & diversity but not until 30 million years ago there existed a gigantic sort of Rhino-Giraffe beast surpassed with having 5m tall, 7and 1/2 m long, bagging the title of the biggest mammal that has ever walked on earth.
Factors that limit the mammals from being gigantic
According to scientists, the factors that limit the mammals for being gigantic in size are:
- Mammals give birth to live young ones.
According to a case study, a mother dinosaur will give birth to tons of eggs and then wander away. On the other hand, a mammal is ought to take care of the living being inside it. Additionally, mammals of massive size have a long gestation period for instance an elephant is pregnant for 2 years. As we know the longer the pregnancy, the dangerous it is for mother and the child.
- The climate of earth plays an important role as well.
Sauropods grew gigantic because of the favorable climate but with the change in the environment, herbivores did not grow so much because they don’t live in such prime conditions.
- Modern mammals are further limited by their skeletal system.
For instance, the fossils of Sauropods show evidence that there were avian-like sacs that are generally invented for a lighter skeleton than one could expect. For a matter of fact, these dinosaurs may have been long enough but on an estimate, they would have weighed around 40 tons. On the contrary, the mammals of modern times with the same size would have weighed twice what Sauropods were.
- The mega mammals of that time would eat their own tissue from inside.
Since mammals are warm-blooded and reptiles are cold-blooded, no matter what some debate suggest about dinosaurs being warm-blooded or cold-blooded, it is a generally known fact that they use way more energy. This emphasizes that the mammals of modern tines cannot be gigantic without cooking their own tissue from within!
Now that you have all the information you need, we hope that you have the answer you were looking for and are satisfied with it.