9 Interesting Facts About Crocodiles

Crocodiles

Facts about crocodiles
13 Jun, 2024

The term ‘Crocodile’ is often used to indicate other members of the ‘Crocodilia’ order, including alligators, caimans, gharial, and false gharial. However, crocodiles possess unique traits that set them apart from their fellow mates and unveil the fascinating background of this aquatic reptile. 

Are you eager to learn more about these formidable creatures? This comprehensive guide unveils nine lesser-known yet fascinating facts about crocodiles, offering insight into their captivating world.

9 Interesting Facts About Crocodiles

1: There Are 23 Different Species of Crocodiles

The reptile order, Crocodilia entails 23 different species, each with their own unique habits and habitat.

  1. American alligator: This species is a native of the Southeastern United States and lives in freshwater. 
  2. American crocodile: Majorly found in America (North and South), the American crocodile can tolerate saltwater with the support of salt glands under their tongue.
  3. Australian freshwater crocodile: Also known as Johnstone’s crocodile or freshie and inhabitant of northern Australia, the Australian freshwater crocodiles are not-man-eaters.
  4. Black caiman: This massive crocodile prefers to live in slow-moving rivers, lakes, the Amazon basin, and other freshwater areas of South America. 
  5. Broad-snouted caiman: This species is typically seen in eastern and central South American countries and stays in slow-moving freshwater land. 
  6. Chinese alligators: Chinese Alligators or Yangtze Alligators are also known as Muddy Dragon, native to China. 
  7. Cuban crocodile: Extreme hunting has caused the International Union for Conservation of Nature (IUCN) to list this dangerous species as Critically Endangered (CE). It lives in freshwater swamps, rivers, and marshes. 
  8. Cuvier’s dwarf caiman: This small-sized species, often kept as a pet in captivity, is distributed in northern and central South America. 
  9. Dwarf crocodile: This African creature and the smallest living freshwater crocodile species is mainly nocturnal and timid. 
  10. Malayan gharial: Also known as False Gharial or Sunda Gharial, prefers freshwater bodies and is currently listed as Vulnerable by ICUN.  
  11. Gharial: This is a native species of the northern Indian subcontinent and is known as the longest freshwater crocodile. 
  12. Yacare caiman: Residents of South American countries, these freshwater creatures prefer living in rivers, swamps, and lakes.
  13. Morelet’s crocodile: The Morelet’s crocodile, or Mexican crocodile, is a freshwater creature primarily found in the Atlantic regions of Mexico, Belize, and Guatemala. 
  14. Mugger crocodile: This  ‘Vulnerable IUCN status’ holder got its name from Indian mythology and prefers floating in freshwater. 
  15. New Guinea crocodile: This is another small crocodile species primarily found in the northern part of New Guinea island, listed as ‘Least Concern.’
  16. Nile crocodile: This is the second-largest extant reptile after the saltwater crocodile and is Africa’s first freshwater predator. 
  17. Orinoco Crocodiles: This ‘Critically Endangered’ crocodile prefers freshwater and is typically in Colombia and Venezuela. 
  18. Philippine crocodile: Also called the Mindoro crocodile, the Philippine Crocodile is one of the two Filipino crocodiles found in the Philippines. 
  19. Saltwater crocodiles: This ‘Least Concern’ status holder is distributed worldwide, including on India’s east coast, northern Australia, Sundaic regions, and Micronesia. 
  20. Schneider’s dwarf caiman: This native of the Amazon and Orinoco basins of South America is the second-smallest alligator after Cuvier’s Dwarf Caiman.
  21. Siamese crocodile: This medium-sized freshwater species is native to Asian countries like Indonesia, Brunei, Malaysia, Myanmar, Etc. 
  22. Spectacled caiman: This Latin American species has a spectacle-like ridge between its eyes, which inspired their name.
  23. West African slender-snouted crocodile: One of five crocodile species in Africa, the ‘Critically Endangered’ West African slender-snouted crocodile prefers to live in dense, vegetated bodies of freshwater.

2: Crocodiles Have Ancient Lineage

Among various facts about crocodiles, their ancient lineage stands out as one of the most intriguing chapters. Tracing their roots back to 240 million years ago, these “living fossils” have remarkably remained relatively unchanged for over 200 million years. In fact, crocodiles even survived the impact of asteroids that led to the extinction of dinosaurs, showcasing their remarkable resilience and adaptability. 

During the Mesozoic Era, crocodiles were at the top of the food chain before humans held that position. 

3: Crocodiles Have Powerful Jaws

Despite possessing relatively weak and highly sensitive jaw muscles, crocodiles boast the strongest bites in the animal kingdom. A Saltwater crocodile holds the record with a jaw pressure of 3700 pounds per square inch (PSI), while a Nile Crocodile’s bite is estimated to range between 4000 to 5000 PSI. In simpler words, a saltwater crocodile can bite with nearly three times higher forces than a lion or tiger.  

4: Crocodiles Can Regenerate Their Teeth

Like alligators, crocodiles also follow a unique tooth-replacement system, replacing those that fall out. A specialized groove in their jaws facilitates this process, allowing new teeth to continuously grow throughout their lifespan. So, this mechanism can generate thousands of teeth over the course of a crocodile’s life.

Recent photos of a crocodile skull’s cross-section from the Senckenberg Museum in Frankfurt have revealed an even more fascinating aspect of crocodile dental anatomy. These images demonstrate that crocodiles have additional teeth growing inside their existing teeth, further highlighting the intricacies of their tooth-replacement system. 

5: Crocodiles Are Carnivores

Crocodiles are primarily carnivores, with their diet consisting predominantly of small creatures like insects, crustaceans, snails, small fishes, frogs, tadpoles, and even wild mammals. They are occasional man-eaters; such incidents typically occur when crocodiles perceive humans as threats and defend themselves.

Surprisingly, despite being carnivores, crocodiles can also be a little Frugivorous! A publication in the Journal of Zoology’s print edition has penned down that nearly three-quarters of the crocodilian species eat fruits frequently and intentionally. 

6: Crocodiles Can Hold Their Breath Underwater

As much as you delve deeper, you will get shocking facts about crocodiles, and holding their breath underwater for more than an hour is one of them. Yes, crocs can hold their breath for more than an hour while they submerge underwater. But how do they make it possible? The physiological adaptations are due to the specialized heart and a unique metabolic system. 

Crocodiles possess a four-chambered heart like humans, with a similar blood circulation process. However, what sets crocodiles apart is the presence of a small opening between their left and right aorta, known as the Foramen of Panizza. This allows blood to bypass the lungs while they submerge. As a result, the heart rate can fall to 2 to 3 beats per minute and save energy with reduced cellular respiration. 

7: Crocodiles Can Sleep With One Eye Wide Open

Yes, crocodiles look witty while sleeping because they keep one eye open. This tendency, known as unilateral eye closure (UEC), is commonly observed in birds and some aquatic mammals.     

Sleeping with one eye open occurs if one side of the brain remains awake and the other side sleeps. During this stage, the open eye is neurologically connected to the wakeful part of the brain and this behavior is known as Unihemispheric Sleep. Crocodiles employ this tactic to remain constantly vigilant of their prey and predators.  

8: Crocodiles Hunt About 1000 People Every Year

Typically, crocodiles are not man-eaters, and their attacks are occasional and opportunistic. However, this opportunistic event results in around 1000 human fatalities every year. Saltwater crocodiles and Nile crocodiles are the most well-known species for killing humans annually. 

9: Crocodiles Are Cold-Blooded

Like other reptiles, snakes, and turtles, crocodiles are ectothermic or cold-blooded, which means they rely on external sources to regulate body temperature and cannot maintain a constant internal heat. Crocodiles prefer a body temperature range of 86°F (30°Celsius) to 91.4°F (33°Celsius). Consequently, they move between warm and cool environments, including basking in the sun to heat up and seeking shade to prevent overheating.

Conclusion

So, from their ancient lineage to their cold-blooded nature, the facts about crocodiles discussed above showcase fascinating evolution as reptiles and their resilience. However, there is growing concern about the decline in their population due to changes in human occupation and land use. Various crocodilian species are facing overhunting, primarily for their valuable skins. Therefore, as consumers and modifiers, humans must rectify our activities to protect the ecosystem.

FAQs

What are 5 interesting facts about crocodiles?

1. There are 23 different species of Crocodiles.
2. Crocodiles have an ancient lineage and emerged  240 million years ago. 
3. Crocodiles have powerful jaws and can bite with nearly three times higher forces than a lion or tiger.  
4. Crocodiles can regenerate thousands of teeth in a life cycle. 
5. Crocodiles are carnivores but are also rarely seen eating fruits.

Do crocodiles have 100 teeth?

The number of a crocodile’s teeth depends on its species. For example, a Dwarf Crocodile can have 60 teeth, while a Gharial possesses 110 at a time.

How long can a crocodile hold its breath?

Crocodiles can spend more than an hour underwater holding their breath. The physiological adaptations are due to the specialized heart and a unique metabolic system.

Are crocodiles carnivores?

Yes, crocodiles are strongly carnivores and prefer to eat insects, crustaceans, snails, small fish, frogs, tadpoles, and even wild mammals. However, they are also occasionally seen intentionally eating fruits.

Are crocodiles cold-blooded?

Yes, crocodiles are cold-blooded and cannot regulate their body’s temperature; hence, they rely on external sources to balance the heat.

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