10 Modern-Day Animals with the Strangest Evolutionary Backgrounds


Though almost universally accepted in the world of science, the story of evolution is far from predictable, which is why some animals have the strangest evolutionary backgrounds.

Evolution is all about the survival of the fittest in a world that ceaselessly throws in a vast array of challenges from climate change to space-born catastrophes to human intervention itself. That’s why the story of evolution is one characterised by constant surprises and unexplained anomalies. Clearly, it’s a story that will never fully be told. Nonetheless, over the past century, scientists have uncovered some spectacular answers to baffling questions. Some of those include revelations concerning even the most common animals. In today’s article, we’ll be looking at ten such creatures which have taken unusual paths through the long history of evolution.

#1. Camels – Unusual Origins

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Camels are typically associated with hot desert climates, while their South American relatives, alpacas and llamas are abundant throughout the Andes Mountains. What’s unique about the entire family, however, is that their current distribution is almost the exact opposite of their place of origin. The first camelids appeared in North America during the Eocene Epoch around 45-million years ago. They remained there until as recently as 2-million years ago. For example, fossils of the Pliocene high arctic camel have even been found as far north as Ellesmere Island, Canada, although the region was far warmer when it lived 3.4-million years ago.

#2. Dolphins – Perfect Convergence

DolphinsPixabay

Like all cetaceans, dolphins have an unusual evolutionary history in that they, being mammals, evolved from land-dwelling creatures that now have far more in common with fish in terms of their environmental niche. Even more bizarrely, dolphins belong to the same order as camels, and their ancestors walked on four legs until some 50-million years ago. Today, they share a morphology more like sharks and the long-extinct ichthyosaurs, despite belonging to a biological class separated by hundreds of millions of years of evolution. It’s a perfect example of what scientists describe as convergent evolution – how organisms adapt to the environments around them.

#3. Platypuses – Mammalian Prototypes

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When Europeans first laid eyes on the platypus in 1797, they thought it was a joke. After all, it’s a mammal that lays eggs and has only one orifice for both reproduction and digestion. Just for good measure, it also has venomous spurs in its hind limbs and uses electrolocation to detect prey. In other words, it’s the most bizarre animal on the planet. However, in terms of evolutionary history, we regular mammals are perhaps the greater anomaly – platypuses are monotremes, the oldest group of mammals by far. Though platypuses themselves haven’t been around for so long, they retain the same traits that all mammals once had when they appeared 210 million years ago.

#4. Coelacanths – Unexpected Survivors

CoelacanthCitron / CC-BY-SA-3.0

Coelacanths are an iconic prehistoric fish that first appeared during the Devonian Period, long before the dinosaurs. Fossils of the fish were first discovered in 1839, and it was assumed that for the next hundred years that the fish disappeared along with the dinosaurs 66-million years ago. Naturally, it came as quite a surprise to the world of science when the fish were rediscovered in 1938 off South Africa. However, there remains a huge gap in the fossil record, leading the coelacanth to not only be labelled a fossil animal, but also a perfect example of a Lazarus taxon. To this day, a great deal of mystery surrounds the fish, and they’re also extremely rare.

#5. Sponges – Ancient Animals

SpongesPixabay

Although microbial life has existed on Earth for far longer, the first animals appeared around 665-million years ago when the world was frozen over during the Cryogenian Period. Some time shortly after then, the first animals for which we have solid fossil evidence started appearing. The humble sea sponge was one of them, alongside its distant relative the comb jelly. A diverse group of entirely sessile organisms, sponges are nonetheless extremely successful, having formed the backbone of our maritime ecosystems for hundreds of millions of years. On top of that is the fact that some species, specifically the glass sponges, live up to 10,000 years.

#6. Pandas – Reluctant Carnivores

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Pandas belong to the carnivoran order, which they share with all other bears as well as dogs, cats, hyenas and the long-extinct beardogs. Though they retain many of the traits typical of carnivores, their diet consists of 99% bamboo. However, they may on rare occasions eat small animals like rodents or birds, which technically makes them omnivores like other bears, most of which are opportunistic predators. While pandas are only found in China, a recent discovery suggests that they may have originated in Europe. Although fossil pandas exist from 8-million years ago in China, the teeth found in Hungary in 2017 are some 2-million years older.

#7. Pronghorns – False Antelopes

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Native to interior regions of western and northern North America, pronghorns are commonly referred to as antelopes. However, despite their similar appearance, they are separated by up to 20-million years of evolution. Pronghorns are the only extant species within their family, with their closest living relatives being giraffes and okapi, both of which are only found in parts of Africa. True antelopes, by contrast, belong to the order bovidae, which they share with cows, sheep and goats. Nonetheless, they all share similar biological niches, making them another example of convergent evolution.

#8. Horses – Tiny Ancestors

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Members of one of the oldest of the major mammal families, horses have ancestors dating back 54-million years. First appearing in the Eocene, equids were diminutive creatures no larger than domestic cats. Bearing little resemblance to their modern counterparts, the animals nonetheless occupied a similar biological niche, yet on a smaller scale. During the first 30-million years of their existence, they competed with the hyracodonts, a different family that more closely resembled modern horses than the prehistoric equines of the time. As they evolved, they grew larger and more diverse before coming to dominate their niche following the extinction of the hyracodontids some 26-million years ago.

#9. Horseshoe Crabs – Forever Unchanged

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If there’s one living animal that truly is a window to the past, it’s the horseshoe crab. First appearing during the Late Ordovician Period some 450-million years ago, the species has lived alongside the earliest land-dwelling life, the dinosaurs and the first mammals. Even more remarkable is the fact that modern specimens are almost identical to their ancient ancestors, thus making them one of the best examples of a living fossil. Furthermore, despite the name, they’re not really crabs at all. Instead, they belong to the order Xiphosura and are the only surviving members of that group. Crabs, by contrast, have only been around since the Jurassic Period, making them some 300-million years younger.

#10. Humans – Creators and Destroyers

Humans and technologyPixabay

The most recent ancestor to all humans lived only 239,000 years ago, which makes us fairly new on the scene compared to most other extant species. What makes us unique, however, is that we’re probably one of the few species that has stopped evolving – at least in natural terms. Our intelligence as a species has effectively allowed us to break away from the grip of evolution. For better or for worse, and empowered by our technology, we’re now in control of our own future like no other species before. However, while on one hand, we’re creators and innovators, we’re also largely responsible for the world’s sixth mass-extinction event – the Anthropocene Extinction.

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Evolution is rarely predictable, as these examples show. Shaped by the natural world around them and the successes and failures of their competitors, animals, along with all other organisms, change over time to the extent they can become unrecognisable within a few million years. What do you consider the most unusual stories in the history of evolution? Share your thoughts in the comments!

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