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Fossils Reveal How and When Giraffe Necks Grew Long

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It turns out the secret to the evolution of the giraffe’s long neck has been sitting in museums for the last hundred years. In a recent study published in the journal Royal Society Open Science, scientists collected and analyzed 71 ancient fossils, originally discovered in the late 19th and early 20th centuries, and dispersed throughout museums in England, Austria, Germany, Sweden, Kenya, and Greece.

Using fossilized vertebrae from nine extinct and two living species in the giraffe family, they charted out the process of neck elongation, which they discovered occurred in two stages, millions of years apart. They found that the first stage of elongation occurred around seven million years ago in a now-extinct genus of giraffe called the Samotherium

They also found that the animal’s neck vertebrae stretched first toward the head, then several million years later, toward the tail. The evolution, however, wasn’t consistent. That is, not all ancient species within the giraffe family experienced both stages of elongation. 

Giraffe anatomy expert Nikos Solounias explained in a press statement, “First, only the front portion of the C3 vertebra lengthened in one group of species. The second stage was the elongation of the back portion of the C3 neck vertebra. The modern giraffe is the only species that underwent both stages, which is why it has a remarkably long neck."

The researchers also discovered that the earliest giraffe specimens started out with a slightly elongated neck. Melinda Danowitz, a medical student who participated in the project, said in the statement, “The lengthening started before the giraffe family was even created 16 million years ago.” 

Interestingly, the okapi, which is the only other living member of the giraffe family, underwent the opposite transformation: As the giraffe's neck was stretching, the okapi's neck got shorter. Now, according to Danowitz, it's one of four species with a "secondarily shortened neck."  

[h/t: Science Daily]

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Animals
Where Do Birds Get Their Songs?
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Birds display some of the most impressive vocal abilities in the animal kingdom. They can be heard across great distances, mimic human speech, and even sing using distinct dialects and syntax. The most complex songs take some practice to learn, but as TED-Ed explains, the urge to sing is woven into songbirds' DNA.

Like humans, baby birds learn to communicate from their parents. Adult zebra finches will even speak in the equivalent of "baby talk" when teaching chicks their songs. After hearing the same expressions repeated so many times and trying them out firsthand, the offspring are able to use the same songs as adults.

But nurture isn't the only factor driving this behavior. Even when they grow up without any parents teaching them how to vocalize, birds will start singing on their own. These innate songs are less refined than the ones that are taught, but when they're passed down through multiple generations and shaped over time, they start to sound similar to the learned songs sung by other members of their species.

This suggests that the drive to sing as well as the specific structures of the songs themselves have been ingrained in the animals' genetic code by evolution. You can watch the full story from TED-Ed below, then head over here for a sample of the diverse songs produced by birds.

[h/t TED-Ed]

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Animals
Watch the First-Ever Footage of a Baby Dumbo Octopus
NOAA, Wikimedia Commons // Public Domain
NOAA, Wikimedia Commons // Public Domain

Dumbo octopuses are named for the elephant-ear-like fins they use to navigate the deep sea, but until recently, when and how they developed those floppy appendages were a mystery. Now, for the first time, researchers have caught a newborn Dumbo octopus on tape. As reported in the journal Current Biology, they discovered that the creatures are equipped with the fins from the moment they hatch.

Study co-author Tim Shank, a researcher at the Woods Hole Oceanographic Institution in Massachusetts, spotted the octopus in 2005. During a research expedition in the North Atlantic, one of the remotely operated vehicles he was working with collected several coral branches with something strange attached to them. It looked like a bunch of sandy-colored golf balls at first, but then he realized it was an egg sac.

He and his fellow researchers eventually classified the hatchling that emerged as a member of the genus Grimpoteuthis. In other words, it was a Dumbo octopus, though they couldn't determine the exact species. But you wouldn't need a biology degree to spot its resemblance to Disney's famous elephant, as you can see in the video below.

The octopus hatched with a set of functional fins that allowed it to swim around and hunt right away, and an MRI scan revealed fully-developed internal organs and a complex nervous system. As the researchers wrote in their study, Dumbo octopuses enter the world as "competent juveniles" ready to jump straight into adult life.

Grimpoteuthis spends its life in the deep ocean, which makes it difficult to study. Scientists hope the newly-reported findings will make it easier to identify Grimpoteuthis eggs and hatchlings for future research.

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