Why Do Marine Iguanas Sneeze
Table of Contents
The majority of the world’s iguanas belong to land species, the only exception being the marine iguana of the Galapagos. This creature is unique in its choice of habitat, but not only: marine iguanas display some truly amazing forms of behavior, such as sneezing, even! Let’s take a closer look at them!
Scientists think that marine iguanas have evolved from land species about 8 million years ago. The Galapagos archipelago gave home to large iguana populations, and today’s marine iguanas are thought to originate from the islands that submerged.
Marine iguanas have developed some extraordinary features to adapt to the special conditions of living in salt water habitats. These medium-size lizards – adult iguanas can grow to be 3 m long – forage exclusively on marine algae. They prefer algae that live in areas where the water is colder – there are 4-5 species that they prefer, mostly red algae -, therefore iguanas have developed unique thermoregulatory features and behaviors to maintain their body temperature constant. The iguana’s body displays other features that serve life in marine habitats as well: the nose is blunt, making it suitable for feeding on seaweeds, the limbs are strong and clawed to allow the iguana to climb rocks and the tail is flat to make swimming more effective.
Adaptability is certainly the characteristic that helped iguanas survive millions of years and the feature that helps them endure the changes in their environment today. They are able to adjust to changes in food availability, switching to algae other than their favorites and they are able to adapt to changing conditions on the long run, too. A long-term research that studied the El Nino effect in the Galapagos area found that marine iguanas have become about 20% shorter to be able to cope with food scarcity. In La Nina periods, when algae are more abundant, iguanas increased their body size again.
The special feeding habits of the marine iguana have brought about interesting changes in the ways these animals digest food and eliminate waste as well. They have developed special glands called salt glands to be able to cope with the excess salt ingested with their food. The gland is located just above the iguana’s eyes and it is responsible for filtering the salt out of the animal’s bloodstream and eliminating the sea salt collected. Iguanas practically sneeze out the excess salt through these salt glands, spraying it out in the form of a salty fluid. After sneezing, the fluid eliminated usually falls back on the lizard’s head, drying there and forming a strange-looking salty crust.
Marine iguanas eat almost exclusively underwater. They are able to dive up to 30 m deep in search of algae beds and they have developed the amazing ability to hold their breath for 45 minutes. After feeding, they usually digest their food on the rocky coast, in the sun, because they are cold blooded and they need to warm up. Their colors also help them absorb the heat coming from the sun – most of them are of a dark grayish-brown shade, with only the males displaying brighter colors during the mating season.
Why Do Marine Iguanas Sneeze?
Have you ever wondered about the peculiar behavior of marine iguanas that involves them sneezing almost incessantly? It’s not because they have a cold or are allergic to something in their exotic Galápagos habitat. This distinctive behavior is a fascinating adaptation to their unique lifestyle, one that involves foraging for food in the salty sea. The marine iguana, or Amblyrhynchus cristatus for those inclined towards scientific names, has evolved a special mechanism to deal with the excess salt that accumulates in their body from their diet. Let’s dive into the sneezy world of marine iguanas and uncover the science behind this unusual phenomenon.
The Salt-Excreting System of Marine Iguanas
Understanding Nasal Gland Functionality
Marine iguanas have a specialized gland located near their noses, aptly named the nasal gland. This gland is a marvel of evolution, allowing these reptiles to filter out the salt from their bloodstream, which accumulates due to their diet of marine algae. The process is quite efficient; the gland extracts the salt from their blood and forms a concentrated solution, which is then expelled through the nostrils. This results in the characteristic sneezing, which is not a sign of discomfort but rather a necessary bodily function to maintain their salt balance.
The Role of Osmoregulation
Osmoregulation, a term that might sound complex, simply refers to the process by which living organisms maintain the balance of water and minerals in their body. For marine iguanas, this involves managing the high levels of salt intake from their aquatic diet. The sneezing mechanism is a part of this broader process of osmoregulation, showcasing the iguana’s ability to adapt to its saline environment. By expelling excess salt through sneezing, these iguanas prevent the potential harmful effects of hypernatremia, an excessive salt condition in the blood.
Adaptations to Marine Life
Dietary Habits and Salt Intake
Marine iguanas are unique among iguanids because they have adapted to a life that involves diving into the ocean to graze on algae. This diet is rich in nutrients but also in salt, which could be detrimental if it weren’t for their ability to sneeze out the excess. This adaptation allows them to exploit a food source that is relatively untapped by other land animals, giving them a niche in their ecosystem.
Evolutionary Traits for Marine Foraging
The sneezing of marine iguanas is just one of the many adaptations these creatures have developed for their marine lifestyle. Their flattened tails and strong limbs are perfect for swimming, while their sharp claws enable them to cling to rocks amidst strong ocean currents. These physical traits, coupled with their unique salt-excretion mechanism, highlight the iguanas’ evolutionary journey from land-dwelling creatures to adept marine foragers.
Behavioral and Environmental Influences
Seasonal Variations in Sneezing Patterns
The frequency and intensity of marine iguana sneezing are not constant and can vary with environmental conditions. During the warm season, when algae are more abundant and iguanas consume more, the sneezing is more frequent. This pattern underscores the direct link between their diet, salt intake, and the need to expel excess salt, showcasing the dynamic nature of this biological function in response to changing environmental conditions.
Impact of Habitat on Salt Excretion
The habitat of marine iguanas, primarily the rocky shores and beaches of the Galápagos Islands, plays a significant role in their sneezing behavior. The proximity to the ocean means a constant battle against salt accumulation, not just from their diet but also from the sea spray and immersion in saltwater. This environmental aspect emphasizes the importance of the nasal gland’s role in their survival and well-being.
Conclusion
The sneezing of marine iguanas is a remarkable example of how animals adapt to their environments. This unique behavior is a testament to the intricate balance of life and the evolutionary innovations that ensure survival. Understanding these adaptations not only provides insights into the fascinating world of marine iguanas but also highlights the interconnectedness of life forms and their habitats.
FAQs
Why do marine iguanas sneeze so much?
Marine iguanas sneeze frequently to expel excess salt from their bodies, which accumulates due to their salt-rich diet of marine algae. This is a necessary adaptation to their unique lifestyle of foraging in the sea.
How do marine iguanas get rid of the salt from their bodies?
They have a specialized nasal gland that filters salt from their bloodstream and concentrates it into a solution that is expelled through sneezing. This process is essential for maintaining their salt balance and overall health.
Does sneezing harm marine iguanas?
No, sneezing is a normal and healthy bodily function for marine iguanas. It’s their way of getting rid of excess salt and is not harmful to them. In fact, it’s a vital adaptation for their survival in a saline environment.
Can all iguanas sneeze out salt, or is it just marine iguanas?
This salt-excreting mechanism is unique to marine iguanas. Other iguana species do not have this adaptation because they do not have the same dietary habits or live in similar saline environments as marine iguanas.
How does the environment affect the sneezing patterns of marine iguanas?
The sneezing patterns of marine iguanas can vary with seasonal changes, particularly with the availability of algae. During warmer seasons when algae are abundant, and their salt intake is higher, marine iguanas tend to sneeze more frequently to expel the excess salt.