MOA-NALO
When and how did they become extinct?
These birds went extinct about 1,000 years ago.
What city did they dwell in?
Their relics have been found on all the bigger Hawaiian islands.
(Moa-Nalo—The Hawaiian Islands were previously home to many species of the enormous, flightless ducks known as moa-nalo.)
The Hawaiian island chain is the world's most remote archipelago, located approximately 3,700 km from the United States mainland. The Hawaiian islands arose from beneath the seas and are effectively the crowns of submarine volcanoes that grow in height and area as they expel their highly runny lava. These landmasses were swiftly colonized by living creatures after they appeared. The wind can transport bacteria, plants, fungus, and small animals, and the waves deposit additional pioneers. Birds, with their ability to fly, were most likely the first large animals to reach uncolonized islands, and one group of these animals that arrived in Hawaii evolved into odd creatures. The moa-nalo were a group of flightless, goose-like birds that existed on all of the main Hawaiian Islands. Because moa means "fowl" and nalo means "lost," their Hawaiian name translates to "lost fowl." The remains of these birds have been discovered in sand dune blowouts, where the wind has exposed their bones, as well as sinkholes and lava tubes, both of which are likely natural traps. These bones indicate that these birds weighed about the same as a swan but were much stockier, with a robust pelvis and muscular, thick legs. Moa-nalo also possessed unusually huge bills that have been compared to the horny jaws of the gigantic tortoises that live in the Galápagos Islands and certain Indian Ocean islands.
The moa-nalo may have had powerful bills and strong legs, but their wings were small structures that served little purpose in flight. The moa-nalo, like the moa of New Zealand, the dodo of Mauritius, and the elephant bird of Madagascar, had no need for flight because there were no significant predators on the Hawaiian Islands. In this predator-free environment, the birds abandoned flight and evolved into enormous, ground-dwelling beasts.
What did these strange birds eat? Coprolites are among the various moa-nalo remnants that have been discovered. (fossilized droppings). These droppings have been investigated, and it appears that the moa-nalo were plant-eating specialists. They most likely waded around the lush Hawaiian Islands munching on various low-growing plants. Some moa-nalo species' beaks even have serrations that operate like teeth, allowing them to take beakfuls of tough plants. Plant cell contents are nutritious, but they are encased in a strong cellulose wall that mammals cannot digest because they lack the ability to create the enzyme cellulase. Any plant-feeding animal, including moa-nalo, must seek the cooperation of microorganisms to get at the goodness inside plant cells. The moa-nalo, like horses and rabbits, were hind-gut fermenters. The soup of mashed up plant materials and digestive fluids came into contact with the symbiotic, cellulase generating microorganisms in the back of their digestive tract. The discovery that many varieties of native Hawaiian plants are well protected with thorns and prickles provides additional support for moa-nalo as plant eaters. Such defenses appear to be a luxury on an island with no major natural herbivores, but they are likely relics of a time when these plants were at the whim of these plant-nibbling birds that ranged all throughout Hawaii.
Following the finding of moa-nalo remains, it was unknown what kind of bird they were. They were goose-like in size and proportion, but the bones of the moa-nalo were more like ducks. Today, we can extract DNA from long-dead bones and compare it to DNA from live species to form a family tree and determine how long a species has existed. Although ancient DNA cannot provide 100% exact answers, it can provide reasonable approximations and possibilities. The DNA isolated from moa-nalo bones revealed that these birds were linked to ducks and that its progenitor arrived in the Hawaiian Islands around 3.6 million years ago. Who was their forefather? It's difficult to say for sure, but some researchers believe the Pacific black duck or a now-extinct related species are possible contenders. The Hawaiian Islands were a beautiful paradise 3.6 million years ago, with no large browsing mammals, thus the progenitors of the moa-nalo migrated between the islands and evolved to fill this void.
We may almost certainly attribute the extinction of the moa-nalo to humans, as has the extinction of several other flightless birds during the last couple of millennia.
Anthropologists disagree over when humans first arrived in Hawaii, but Polynesians have been there since at least a.d. 800. The moa-nalo, like the dodo, was exceedingly easy to hunt. They had never seen a person and hence had no natural dread of our extremely hazardous species. Moa-nalo were huge birds (4–7 kg) that were likely highly valued by Polynesian hunters. Because the moa-nalo evolved in the absence of predators, there was no need for them to reproduce rapidly in order to balance out the death rate. They were most likely long-lived, slow-growing birds with a low reproductive rate. The other major issue that humans introduced to Hawaii was a slew of nonnative animals (dogs, cats, sheep, goats, pigs, and so on). These competed for food with the moa-nalo, damaged their nests, and even ate their eggs. Despite having lived unmolested in the Hawaiian Islands for more than 3 million years, the moa-nalo were likely driven to extinction in as little as 200 years after the first humans arrived in this volcanic archipelago.
• Because Hawaii is so isolated from other landmasses, a wide range of unusual animals have evolved there. The birds were extremely diverse, and a few ancient colonists who arrived from faraway beaches gave rise to a plethora of species, many of which are now sadly extinct.
• It is assumed that the original colonists were represented by 15 species, which evolved into roughly 78 species during a short period of geological time, albeit this number is much greater if we add species known exclusively from bones, such as the moa-nalo.
• More than 56 bird species have become extinct since humans colonized Hawaii, and many of the remaining native species are critically endangered. Some of these species are assumed to have died as a result of avian malaria, which was introduced to the islands by nonnative birds brought by humans.
HORNED TURTLE
(Horned Turtles—With their spiked heads and tails, horned turtles are among the largest and strangest turtles to have ever lived.)
When was it declared extinct?
The last of these turtles is considered to have died off around 2,000 years ago.
Where did it spend its time?
The bones of these ancient turtles were discovered on Lord Howe Island, 600 km from mainland Australia and the New Caledonian islands.
Because of the familiarity of these odd animals, very few individuals would fail to recognize a turtle. Although the fossil record is replete with strange species, turtles are thought to be among the weirdest vertebrates to have ever lived. Although its skeleton has the same bones as any other vertebrate, they are assembled in a fundamentally different manner. Their bodies are shielded by a bony shell, which is effectively a massively modified rib cage. The exterior carapace strength varies by species, but it ranges from the leathery dome of soft-shelled turtles to the practically impregnable shell of gigantic tortoises. The hip and shoulder girdles are also unusual in that they are located inside the rib cage. These animals are well known for their ability to retract their heads and legs into the protective confines of their shells. Scientists can distinguish two types of turtles based on how they remove their heads: cryptodires and pleurodires. The latter are sometimes referred to as side-necked turtles because their lengthy necks are bent into a S shape to keep their heads out of harm's way. The turtles used as pets belong to the first group, the cryptodires, and can pull their heads right into their shells by bending their necks below the spine.
There is no doubt that some turtles, particularly the land-dwelling species, are slow, lumbering creatures, qualities that are frequently associated with evolutionary failure and poor adaptability. For the turtles, though, nothing could be further from the truth.
These shelled reptiles are a successful group of creatures that have been present for at least 215 million years (and probably much more), making them significantly older than lizards and snakes. They are not only ancient, but they are also among the only extant reptiles that have become almost entirely aquatic, leaving the water only to lay eggs. (some species of snake also only leave the water to lay eggs).There are around 300 turtle species today, ranging from tiny 8-cm tortoises to the oceangoing giant, the leatherback turtle, which can be 3 m long and weigh 900 kg.
Even while some very unusual turtles are still alive today, they pale in comparison to an enormous, land-living turtle that only fell extinct in the last few thousand years. This was the horned turtle, and it must have been a magnificent creature in its day. The horned turtle was about 2.5 m long and must have weighted a lot. the area of 500 to 700 kg. The largest living land-dwelling turtle is the Galápagos tortoise, which weighs over 300 kg and measures 1.2 m long. Consider a horned turtle next to a Galápagos tortoise to get an idea of the magnitude of this extinct beast. The horned turtle was not only large, but it also had an unusual appearance.
Large horns and spikes sprouted from its skull, the longest of which emerged from the back of the head and could reach a span of 60 cm. The powerful forward Armory was paired with a regular tortoise carapace and a heavily protected tail with spines. The horns of this extinct turtle prevented the head from being pushed within the shell during times of peril. The turtle may have utilized these horns to defend itself, but we don't know what predators lurked on the islands where these extinct reptiles thrived. During the breeding season, male giant turtles can be fairly violent to one another, and it's possible that the extinct giant used its horns and tail spikes to compete with other guys for the privilege to mate. The horned turtles, like other island creatures, may have developed to tremendous size because there were few dangers in their secluded native territory. Large size, on the other hand, is a simple yet effective defense against many predators. The truth is that we will never know the evolutionary force underlying these turtles' remarkable size and look.
We can be more certain about their diet. Large land turtles are slow and hefty. Fast-moving animal prey is therefore out of the question. The Galápagos tortoise and other terrestrial giant turtles are herbivores that eat a vast variety of plant stuff, as we know. The horned turtle was clearly not built for climbing trees or raising up on its hind legs. It must have relied on the unusual, low-growing plants that occur on New Caledonia and the adjacent islands to reach tall vegetation. All living turtles lay eggs, and we can presume that the horned turtle did as well, but how and where it laid them will never be known for definite. Perhaps it dug a pit before laying its eggs and then forgot about it.
It's incredible to imagine that these massive, odd turtles roamed some of the western Pacific's most remote islands until very recently geological eras, but why they died off remains a mystery. We do know that island animals have suffered greatly at the hands of humans, and we can virtually be certain that the first thought of the first human who encountered these shelled giants was, "Can I eat it?" A slow-moving turtle of any size is no match for humans and their arsenal of weapons. Because Lord Howe Island and New Caledonia are small sections of land that could never support significant populations of such large animals, it is extremely likely that when humans discovered the horned turtle, they wiped it off in a matter of centuries, if not decades.
• Aside from the way living turtles bend their necks to hide their heads, we can divide them into three groups: marine forms with flipper-like legs, such as the leatherback turtle; terrestrial forms with thick, pillar-like legs, such as the Galápagos tortoises; and semiaquatic forms, such as terrapins and snapping turtles.
• Because many current turtle species are critically endangered, they may soon join the horned giant in extinction. Some extremely rare species can only be found in small numbers on isolated islands, while oceangoing animals are threatened by fishing hooks, drift nets, and direct hunting. Without comprehensive and aggressive preservation, some of the most spectacular turtles may become extinct over the next 30 years.
• Because turtles live such sluggish lives, they are among the longest-living animals. The Galápagos tortoise has a life expectancy of at least 150 years. Captain Cook delivered a famous, long-lived radiated tortoise to the Tongan royal family in 1777. Tu'i Malila, the tortoise, died in 1965 at the age of 188. The lifespan of a massive turtle like the horned giant can only be estimated.
• There were other prehistoric turtles that were extremely gigantic in the age of the dinosaurs, further back in the fossil record. Archelon, for example, is only known from 70-million-year-old fossils. It was roughly 4 m long, with a 4.5 m spread between its fl ippers. Archelon weighed between 2 and 3 tonnes when fully grown. Its huge head and powerful bite appear to be well adapted to devouring shelled mollusks like the extinct ammonites.
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