Antarctica is swimming in penguins, of many different types and varieties. Among them, though, is a penguin that has defied the odds to become the most populous and common in the world.

With thousands of emperor penguins waddling across the frozen deserts of Antarctica, diving in and out of the warming coastal waters, you'd think that their legions would outnumber all others. Yet, there's another penguin that has managed to hold onto its numbers, becoming the world's most common, yet lesser known, in the world.

So, what is the world's most common penguin? Which of these birds is so populous that it holds the animal world record for having more in its ranks than any other types?

Let's take a look at a special flightless bird with a hilarious name.

The most common penguin type in the world is the macaroni penguin, which won its world record on December 21, 2014, when they had an estimated total population of 6,300,000 breeding pairs. Macaroni penguins are famous for their brightly colored crests, making them not only one of the most common but one of the most beloved penguins out there.

Their populations have significantly declined since the 1970s, largely on account of disappearing ice and various other anthropogenic impacts. Due to this decline, they are listed by the IUCN as "Vulnerable," with a decreasing population trend. It is clear that their main sources of threat are human-based, with an emphasis on fishing practices, climate change, and invasive species.

When Guinness World Records awarded their record in 2014, citing the official population we have listed above, they were referring to the number of breeding pairs. Nowadays, there is more-or-less a total population of about 18 million macaroni penguin individuals in the world.

They are large penguins, though clearly not as big as the famously large emperor penguins, and are found not only on the Antarctic Peninsula, but in at least 200 other areas as well (all in the Antarctic or Subantarctic region). They have even been sighted in small groups on islands a little south of Tasmania, Chile, the Falkland Islands, and elsewhere.

Due to their remarkably bright and colorful crests, they are a favorite among penguin species, second only to the emperor penguin.

There is no specific reason why the macaroni penguin is so common, except to say that they are extremely widespread across the region, with plenty of healthy breeding pairs keeping the population up. It is important to draw attention to the fact that in recent years, macaroni penguins have started to really feel the impacts of climate change.

While many people believe that Lovelace, a beloved character from the 2006 animated flick Happy Feet (voiced by the late, great Robin Williams), is a macaroni penguin. Love face, though, is a rockhopper penguin.

Ultimately, news is generally bad for penguins. While macaroni penguins are the most common in the world, they are simply the luckiest of an unlucky lot, and plenty of work remains to be done to make sure things stay that way.

It would be a mistake to assume that because the macaroni penguin is the most populous and common in the world, it's not at risk. Just recently, the Antarctic region has seen alarming cases of bird flu n. This, as well as the impacts of climate change and melting Antarctic ice, make the future of even the macaroni penguin seem like it's up in the air.

Most penguins aren't officially classified as endangered, but they are at risk. As illness and climate change ravaged their population, scientists are saying that there's a possibility of them suffering the same "biological annihilation" that many animals are facing across the globe.