{"id":31787,"date":"2026-08-11T15:50:00","date_gmt":"2026-08-11T19:50:00","guid":{"rendered":"https:\/\/www.ecoportal.net\/en\/?p=31787"},"modified":"2026-08-11T15:50:00","modified_gmt":"2026-08-11T19:50:00","slug":"glass-frogs-barely-inch-long-make","status":"publish","type":"post","link":"https:\/\/www.ecoportal.net\/en\/glass-frogs-barely-inch-long-make\/31787\/","title":{"rendered":"Glass frogs hide close to 90 percent of their red blood cells inside a mirrored liver while they sleep, and 2 species new to science sit on opposite banks of one Ecuadorian river valley"},"content":{"rendered":"

Turn a glass frog over and you can watch its heart beat<\/strong>.<\/p>\n

Not through a scan. Through the animal itself<\/strong>.<\/p>\n

The belly skin is clear enough to show the heart, the vessels branching off it, the gut, and in a female a string of eggs<\/strong>.<\/p>\n

Most people assume the trick is simply pale skin.<\/p>\n

It is not.<\/p>\n

The real answer is a nightly disappearing act<\/strong> performed on the frog’s own blood.<\/p>\n

Where the blood goes<\/h2>\n

Blood is the problem. Red blood cells are red because they absorb light, so an animal can lose every scrap of pigment in its skin and still glow with a dark red outline<\/strong> wherever its blood is.<\/p>\n

Sleeping glass frogs solve that by getting rid of it.<\/p>\n

When they settle down to rest, close to 90 percent of their red blood cells are pulled out of circulation and packed into the liver. That single move makes the resting animal two to three times<\/strong> more transparent than it is when awake, and the cells flood back into circulation the moment it starts moving again.<\/p>\n

The liver is the clever part. It is lined with reflective guanine crystals<\/strong> that mirror light away from the packed cells rather than absorbing it, so the organ hides a body’s worth of blood without turning into a dark blot in the middle of a see through frog.<\/p>\n

The part that should not work<\/h2>\n

Pack that much blood into one organ and it ought to clot<\/strong>. In almost any other vertebrate it would, which is exactly why the finding interested people outside herpetology.<\/p>\n

These frogs do it twice a day<\/strong> and come to no harm.<\/p>\n

“This is the first of a series of studies documenting the physiology of vertebrate transparency,” said Jesse Delia, the biologist who led the work, “and it will hopefully stimulate biomedical work to translate these frogs’ extreme physiology<\/strong> into novel targets for human health and medicine.”<\/p>\n

There are more than 150 known species in the family, spread through the neotropics and concentrated in the northern Andes and Central America. They spend their nights on leaves above fast moving streams<\/strong>, and their days pressed flat against the green, effectively invisible.<\/p>\n

The father who carries water in his bladder<\/h2>\n

The transparency is not even the strangest thing about them. Males of at least two dozen species look after the eggs, which is rare among vertebrates<\/strong>, and some do it for weeks.<\/p>\n

A clutch stuck to the underside of a leaf dries out fast.<\/p>\n

Some males solve it by simply sitting on the eggs like a hen, keeping them damp by contact. Others go considerably further, and the method is one of the more remarkable things anyone has recorded in an amphibian. “The father searches for dew on leaves, sucks it up into his urinary bladder<\/strong> through a highly vascularized region of the belly, and then transports it to the babies,” Delia said.<\/p>\n

The animal doing this weighs less than a paper clip. It is hauling water<\/strong> in its own bladder, one trip at a time, to keep a clutch of eggs alive until they drop into the stream below.<\/p>\n

Two new species, one valley between them<\/h2>\n

The valley is called the Intag Guayllabamba, and it cuts through the northwestern Andes of Ecuador. Two previously unnamed<\/strong> glass frogs were described from opposite sides of it, less than 12 miles apart in a straight line.<\/p>\n

They look almost identical<\/strong>. The genetics say otherwise.<\/p>\n

One lives in three reserves in the Mashpi river basin at roughly 3,400 to 3,700 feet. The other sits north of the valley in the Tois\u00e1n mountain range<\/strong>, a block of highland partly separated from the main Andean spine, between about 3,900 and 4,650 feet. Populations split by a barrier like that drift apart genetically<\/strong> long before they look different.<\/p>\n

Habitat that gets carved up produces the same effect at speed, which is why development inside a protected range matters, whether the animals involved are frogs or the elephant habitat<\/a> being cleared elsewhere.<\/p>\n

Why the address matters more than the name<\/h2>\n

The paper describing both species does not stop at the description. It flags that populations of both frogs sit inside or immediately beside mining concessions<\/strong>, alongside deforestation the authors call illegal, and the description<\/a> spends real space on it.<\/p>\n

That is not a side note<\/strong> for an animal like this.<\/p>\n

Glass frogs need clean, fast, cool water, because the eggs sit in open air directly above the current and the tadpoles drop into it. Sediment from a road cut, runoff, a few degrees of warming, and the eggs fail first<\/strong>, before anyone notices the adults are gone. Finding where these frogs are calling is a water quality survey<\/strong> that costs nothing.<\/p>\n

Losing them works the same way in reverse, quietly, the way a displaced fox<\/a> vanishes from ground that was built over. Right now a male the size of a thumbnail is sitting on a clutch above a stream, and the transparency study<\/a> explains why you would walk straight past him.<\/p>\n","protected":false},"excerpt":{"rendered":"

Turn a glass frog over and you can watch its heart beat. Not through a scan. Through the animal itself. The belly skin is clear enough to show the heart, the vessels branching off it, the gut, and in a female a string of eggs. Most people assume the trick is simply pale skin. It is not. The … Read more<\/a><\/p>\n","protected":false},"author":28,"featured_media":31855,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"rank_math_focus_keyword":"glass frog","rank_math_title":"Glass frogs hide close to 90 percent of their red blood cells inside a mirrored liver while they sleep, and 2 species new to science sit on opposite banks of one Ecuadorian river valley","rank_math_description":"Two new glass frog species found in Ecuador reveal the creature's strangest secrets: a heart that disappears on cue and a father who carries water in his","footnotes":""},"categories":[83],"tags":[],"class_list":["post-31787","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-earth"],"_links":{"self":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/31787","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/users\/28"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/comments?post=31787"}],"version-history":[{"count":0,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/31787\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media\/31855"}],"wp:attachment":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media?parent=31787"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/categories?post=31787"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/tags?post=31787"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}