Transparent Glass Frogs Can Turn Almost Invisible When They Sleep

A recent study shows the incredible diversity of evolution in amphibians. A tiny species called the glass frog can become almost invisible while sleeping. Its body becomes virtually undetectable: it casts no shadows and even has no blood inside. How does it do it? By enlarging its liver by over 40% to accommodate 89% of its blood cells. Read more about this intriguing amphibian.

Meet Glass Frogs

A glass frog The nocturnal amphibians turn bright red when they’re active. However, while asleep, they become almost transparent. The amphibian’s digestive system, heart, and liver are encased in a sac that mirrors its surroundings. It tremendously assists the frog in achieving transparency.

Researchers who participated in the study were perplexed by how the tiny frogs could do it. Achieving that level of camouflage is truly mesmerizing because our bodies are full of tissues and cells that absorb and scatter light.

Key Points in the Research

The whole study focuses on tissue transparency in glass frogs and how they succeed in the art of “vanishing blood.” Researchers relied on imaging techniques to conduct the study. They had to make images of awake and asleep species.

Photoacoustic microscopy images showing circulating red blood cells within a glass frog while asleep and under anesthesia.

But, as it turns out, if the frogs are under anesthesia or stressed, they don’t turn transparent at all. So, they had to think of a smart solution to make them happily asleep. Fortunately, the first author of the paper, Carlos Taboada, came up with an ingenious plan.

Taboata proposed they rely on non-invasive imaging technology. It’s called photoacoustic microscopy and essentially, it can detect red blood cells using a laser. The frogs’ molecules absorb light from the lasers and release it back in the form of sound waves. Researchers use those to map the bodies of each amphibian.

Everyone on the team was blown away when they discovered the frog species could hide that much blood in its liver. “They don’t just put in some blood; They put all of their blood in that liver,” said Karen Warkentin, a biologist who participated in the study.

The History of Creepy Dolls and Why Kids Adore Them

While many adults are familiar with the creepy doll stereotype that has been popularized in movies and media, they are often surprised when they discover their children love to play with these dolls. It turns out that kids find nothing unusual about dolls like Chucky or other toys that were made to be creepy on purpose.

Children Have No Fear of Dolls

A young girl with her doll

Many adults fear dolls so strongly that it even crosses into a type of phobia called pediophobia. Children do not share this same fear and even enjoy using popular creepy dolls like Ophelia or Chloe Beard. More light was shared on this after parents started sharing their experiences with their kids and their creepy dolls on the Internet. One video shows how a young girl gets a creepy doll as a gift from her aunt and loves it so much she even drops a few tears. The doll is taller than the toddler and has black hair, pale skin, and sunken eyes, but that doesn’t seem to bother her owner at all.

Children Don’t Know Dolls Can Be Creepy

A still from the movie Child's Play

So, why does it seem like some children are immune to the stereotypical creepy doll persona? Well, young children have not been conditioned to understand the meaning of the word creepy and have no idea why they should be scared of a toy. They are actually attracted to such dolls because they are different and allow them to play with their imagination and creativity. Children gravitate towards playing with dolls that mirror a human because it piques their interest and develops their brain and personality.

Dolls Have Been Around for Centuries

Dolls have been available to children for centuries. Wooden paddle dolls were discovered in ancient Egyptian tombs dating back to 2000 BC. In Germany, clay dolls became popular in the 13th century, and French fashionable dolls started appearing in the 14th century. Dolls were also found in other parts of the world and served as companions to many. In recent decades there has also been a fascination with dolls in general, and currently, there are over 40 doll museums across the USA.

The doll Annabelle from the movie with the same name

The concept of the creepy doll apparently stems from modern tiles and particularly from Hollywood and certain scary movies. When dolls became miniature versions of humans, they became a perfect platform for creatives to exploit their qualities of fear and horror. So, genre-defining movies like Annabelle and Child’s Play, featuring the popular Chucky, became the basis for the fears of many adults and could be pointed out as the reason why dolls are considered creepy in modern days. So, it’s no wonder that kids who haven’t seen such movies have no problem scaring their parents with their creepy dolls.