Specimen Showcase | Welcome to Jurassic Park

The American alligator, 𝘈𝘭𝘭𝘪𝘨𝘢𝘵𝘰𝘳 𝘮𝘪𝘴𝘴𝘪𝘴𝘴𝘪𝘱𝘱𝘪𝘦𝘯𝘴𝘪𝘴 (Daudin, 1801), is native to the southeastern United States and inhabits freshwater environments such as swamps, marshes, rivers, and lakes, playing a crucial role in their ecosystems. These alligators are known as the darkest among the 25 species in the crocodilian family and their colour changes throughout their lifespan. As juveniles, American alligators are black with yellow crossbands but as they mature, the yellow fades, revealing an olive-black colouration.

As one of the largest reptiles in North America, these formidable creatures can grow up to an average length of 3.50 m. The largest 𝘈. 𝘮𝘪𝘴𝘴𝘪𝘴𝘴𝘪𝘱𝘱𝘪𝘦𝘯𝘴𝘪𝘴 on record measured 4.369 m, making them the ninth largest crocodile in the world😱. Despite their large size, their limbs are relatively short and thick, which favours their swimming ability.

Crocodiles or alligators? Are those similar or different species and if so how to tell them apart? They are indeed different species which can be distinguished by looking at two main features: the shape of their snout and their teeth/jaw structure. The American alligator has a distinctive snout shape and jaw structure. Most crocodile snouts are pointed, while alligators have round-shaped snouts. Additionally, an alligator's upper jaw is larger than the lower jaw, so only the upper jaw teeth are visible when it closes its mouth🤐. This contrasts with other crocodiles, whose teeth on both jaws are visible even when the mouth is closed.

An American alligator continuously replaces its teeth in its lifespan. With approximately 80 teeth at the same time. These teeth are replaced when they break or fall out. Over their lifespan. an alligator may regrow hundreds of teeth and as many as 3000 teeth! With these formidable teeth, alligators are carnivorous, consuming a wide range of prey, from invertebrates, fish, and birds, to mammals and other reptiles. Their hunting habits vary with age with larger alligators hunting larger prey.

Crocodilian are ectotherms, incorrectly referred to as "cold-blooded," meaning they cannot regulate their internal temperature and rely on external sources☀️ (but which does not mean their blood is cold). American alligators love basking in the sun to regulate their temperature. This behaviour varies seasonally; in summer, basking occurs earlier in the morning and later in the afternoon, while in winter, they bask more frequently or even throughout the whole day. You might have seen videos of huge alligators walking on all fours legs with their tails dragging on the ground, slowly crossing a golf course. This behaviour is called the "high walk," a low-energy form of mobility.

During the mating season, males produce deep bellows to attract females with this sound perceptible as far as 1.5 km away in water! Once mating occurs, females build nests near water out of vegetation and mud, where they lay their eggs🥚.The species exhibits fascinating reproductive behaviour, with sex determined by temperature. About 25-30 days after the eggs are laid, the nest temperature determines the hatchlings' sex: warmer temperatures of 33°C or above produce males, while cooler temperatures of 31°C or below result in females. At around 32°C, the sex ratio is even.

Unlike many reptiles, female alligators care tremendously for their offspring👩🏻‍🍼. They guard the nests from predators, assist the hatchlings, and continue to protect them for up to a year. Here is a fun fact about hatching: when an egg is about to hatch, the baby alligator makes a high-pitched noise inside the egg to alert the mother. The mother then removes the nest materials and helps them hatch. This level of parental investment is rare among reptiles and underscores the alligator's unique approach to ensuring the survival of their young. Male alligators are less involved in parental care; some may stay near the nest, while others might end up eating the offspring😨. If there are records of both parents aiding hatching together in zoos, such behaviour remains unrecorded and unlikely in the wild.

Have you noticed the importance of vocals throughout the alligator’s life? In fact, they are probably the most acoustic reptile animals! Vocal expression plays a significant role throughout their lives, for they communicate with frequencies. Like humans, alligators generate sounds through vibrating vocal folds in the larynx, however, they are capable of altering the frequencies by adapting vocal tract elongation, tissue vibrations, and more! Recent studies on the species suggest that vocal expression has a great contribution to individual identity in Crocodylian animals! These sounds, alongside environmental vibrations, are analyzed by an organ called the integumentary sense organ (ISO). Located in the jaws or scales. ISOs help alligators sense 🧘🏻movements in the water, detect when prey is in contact with their teeth, and identify items in their jaws.

Does the alligator 🐊 raise your interest in ecology and biodiversity? If your answer is positive, come to the Hong Kong Biodiversity Museum where we have two species of alligators and a wide variety of specimens, from sponges to bats, from which you can learn more about their fascinating ecology. If you found this article📝engaging, share it with your friends and stay tuned for our captivating biodiversity narratives released weekly!

Text: Max

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