Illustrator unknown via Wikimedia Commons // Public Domain
Illustrator unknown via Wikimedia Commons // Public Domain

These Fish Can Recognize Human Faces

Illustrator unknown via Wikimedia Commons // Public Domain
Illustrator unknown via Wikimedia Commons // Public Domain

We really need to stop underestimating our fellow creatures. A new study adds a talented tropical fish to the swelling ranks of non-human animals that can tell humans apart. The research was published in the journal Scientific Reports. 

Facial recognition is a vital but complex task—so complex that humans have an entire region in our brains dedicated to it. And because it’s such a sophisticated process, scientists used to assume that we were the only animals that could do it. Then that circle widened a little bit to include other primates. But that circle just keeps growing, and currently includes octopuses, bees, and at least four types of birds. This is, admittedly, kind of strange; with the possible exception of birds, none of these animals have any natural need to tell people apart. 

Nor do fish. And like the cognitive abilities of birds, bees, and cephalopods, fishes’ mental skills have been more or less written off until quite recently. With this fact in mind, a team of researchers from the UK and Australia decided to find out if fish were up to the task. 

One species, the archerfish (Toxotes chatareus), seemed especially well-suited for the experiment. Archerfish are amazing creatures with a super-cool hunting strategy: They wait near the water’s surface for an insect to land on a nearby leaf, then shoot a jet of water at the bug, knocking it into the water. 

Illustration: Pearson Scott Foresman via Wikimedia Commons // Public Domain

Their aim is superb, and their vision acute, which suggests fairly sophisticated mental function. It also makes them great experimental subjects, since they can be trained to choose an object or image by spitting at it. 

The new study consisted of training and two experiments. First, researchers set up a screen above a tank holding a single fish. To see if the fish could tell the difference between two faces, the scientists displayed two faces on the screen, then attempted to train the fish to spit water at only one of them whenever it appeared. The training worked, and quickly, too; within just a few sessions, all the fish had learned to spit at the right face.

Image Credit: Newport et al. 2016.Nature Communications

Then the researchers brought back the same fish and exposed them to lots and lots of faces—44, to be precise. The goal was to see if the fish could still pick out the face they learned in the first round of training. To make it even harder, the researchers then cut all the face images into oval shapes and displayed them in grayscale so the fish couldn’t rely on more obvious cues like face shape or color. 

But the fish didn’t need color or shape. As in their hunting, the archerfish were incredibly accurate when it came to spotting faces. In the first round of 44 faces, the fish subjects averaged 81 percent accuracy. Once the obvious cues were removed they did even better, selecting the right face 86 percent of the time.   

“Fish have a simpler brain than humans and entirely lack the section of the brain that humans use for recognizing faces,” said lead author and Oxford University zoologist Cait Newport in a press statement. “The fact that archerfish can learn this task suggests that complicated brains are not necessarily needed to recognize human faces.”



These Sparrows Have Been Singing the Same Songs for 1500 Years

Swamp sparrows are creatures of habit—so much so that they’ve been chirping out the same few tunes for more than 1500 years, Science magazine reports.

These findings, published in the journal Nature Communications, resulted from an analysis of the songs of 615 adult male swamp sparrows found in six different areas of the northeastern U.S. Researchers learned that young swamp sparrows pick up these songs from the adults around them and are able to mimic the notes with astounding accuracy.

Here’s what one of their songs sounds like:

“We were able to show that swamp sparrows very rarely make mistakes when they learn their songs, and they don't just learn songs at random; they pick up commoner songs rather than rarer songs,” Robert Lachlan, a biologist at London’s Queen Mary University and the study’s lead author, tells National Geographic.

Put differently, the birds don’t mimic every song their elders crank out. Instead, they memorize the ones they hear most often, and scientists say this form of “conformist bias” was previously thought to be a uniquely human behavior.

Using acoustic analysis software, researchers broke down each individual note of the sparrows’ songs—160 different syllables in total—and discovered that only 2 percent of sparrows deviated from the norm. They then used a statistical method to determine how the songs would have evolved over time. With recordings from 2009 and the 1970s, they were able to estimate that the oldest swamp sparrow songs date back 1537 years on average.

The swamp sparrow’s dedication to accuracy sets the species apart from other songbirds, according to researchers. “Among songbirds, it is clear that some species of birds learn precisely, such as swamp sparrows, while others rarely learn all parts of a demonstrator’s song precisely,” they write.

According to the Audubon Guide to North American Birds, swamp sparrows are similar to other sparrows, like the Lincoln’s sparrow, song sparrow, and chipping sparrow. They’re frequently found in marshes throughout the Northeast and Midwest, as well as much of Canada. They’re known for their piercing call notes and may respond to birders who make loud squeaking sounds in their habitat.

[h/t Science magazine]

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5 Fascinating Facts About Koko the Gorilla
ZUMA Press, Inc., Alamy
ZUMA Press, Inc., Alamy

After 46 years of learning, making new friends, and challenging ideas about language, Koko the gorilla died in her sleep at her home at the Gorilla Foundation in Woodside, California on June 21, 2018. Koko first gained recognition in the late 1970s for her ability to use sign language, but it was her friendly personality that made her a beloved icon. Here are five facts you should know about the history-making ape.


Francine "Penny" Patterson, then a graduate student at Stanford University, was looking for an animal subject for her inter-species animal communication experiment in the early 1970s when she found a baby gorilla at the San Francisco Zoo. Originally named Hanabiko (Japanese for "fireworks child," a reference to her Fourth of July birthdate), Koko took to signing quickly. Some of the first words Koko learned in "Gorilla Sign Language," Patterson's modified version of American Sign Language, were "food," "drink," and "more." She followed a similar trajectory as a human toddler, learning the bulk of her words between ages 2.5 and 4.5. Eventually Koko would come to know over 1000 signs and understand about 2000 words spoken to her in English. Though she never got a grasp on grammar or syntax, she was able to express complex ideas, like sadness when watching a sad movie and her desire to have a baby.


Not only did Koko use language to communicate—she also used it in a way that was once only thought possible in humans. Her caretakers have reported her signing about objects that weren't in the room, recalling memories, and even commenting on language itself. Her vocabulary was on par with that of a 3-year-old child.


Koko was the most famous great ape who knew sign language, but she wasn't alone. Michael, a male gorilla who lived with Koko at the Gorilla Foundation from 1976 until his death in 2000, learned over 500 signs with help from Koko and Patterson. He was even able to express the memory of his mother being killed by poachers when he was a baby. Other non-human primates have also shown they're capable of learning sign language, like Washoe the chimpanzee and Chantek the orangutan.


Koko received many visitors during her lifetime, including some celebrities. When Robin Williams came to her home in Woodside, California in 2001, the two bonded right away, with Williams tickling the gorilla and Koko trying on his glasses. But perhaps her most famous celebrity encounter came when Mr. Rogers paid her a visit in 1999. She immediately recognized him as the star of one of her favorite shows, Mister Rogers' Neighborhood, and greeted him by helping him take off his shoes like he did at the start of every episode.


Koko was never able to have offspring of her own, but she did adopt several cats. After asking for a kitten, she was allowed to pick one from a litter for her birthday in 1985. She named the gray-and-white cat "All Ball" and handled it gently as if it were her real baby, even trying to nurse it. She had recently received two new kittens for her 44th birthday named Ms. Gray and Ms. Black.


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