Toad eats earthworm, video


This 16 April 2019 shows a toad eating an earthworm.

It is not easy; the toad has to use even its eyes for it.

Nathan Schrijver made this video in Utrecht province in the Netherlands.

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Costa Rican frogs, new species discovery


A male Warszewitsch's frog in its natural habitat (El Valle de Antón, Panama). Credit: Dr Robert Puschendorf

From ScienceDaily:

The truth about a true frog: Unknown Costa Rican frog hidden amongst a widespread species

The discovery highlights the urgent need of modern DNA tools when studying rapidly declining animal groups like amphibians

April 11, 2019

Known to science since 1857, a common species of true frog (a “true frog” is one assigned to the family Ranidae), found from north-eastern Honduras, through Nicaragua and Costa Rica to central Panama, turns out to have been keeping its “multiple identities” a secret all along.

According to British and Costa Rican herpetologists, who recently used DNA barcoding to study the species in question, what we currently call Warszewitsch’s frog is in fact a group of “cryptic” species. The study, conducted in the Área de Conservación Guanacaste (ACG), Costa Rica, by James Cryer, Dr Robert Puschendorf, Dr Felicity Wynne from the University of Plymouth, and Dr Stephen Price, UCL, is published in the open-access journal ZooKeys.

In their paper, the authors suggest that the well-known Central American frog species, commonly known as the Warszewitsch’s frog, may in fact consist of multiple different “cryptic” species. This phenomenon is well documented among tropical amphibian fauna, where high levels of genetic variation within populations of a single species surpass levels found between different, classified species.

By utilizing a technique known as DNA barcoding, which compares short snippets of DNA sequences between individuals sampled, the scientists analysed specimens from three different geographic areas within Costa Rica and Panama. In this case, the researchers used sequences derived from mitochondria, the energy-producing “power houses” found in animal cells. Their results indicated there was enough genetic variation to suggest cryptic species are indeed present.

The team chose this particular species because cryptic species were previously identified at two Panamanian sites. Now, the samples from Costa Rica broaden the study area, suggesting that there could be multiple species going by the name Warszewitsch’s frog all across its known distribution.

Conservation biologist and lead author James Cryer says:

“The next step will be to gather more samples throughout the full range of the species. Additionally, if we are to fully discern one species variant from another, further studies that compare the physical, behavioural and ecological characteristics of the frogs, alongside more genetic testing is needed.”

Overall, findings like these are important to help improve our understanding of amphibian biodiversity and, thus, work towards its conservation.

“If indeed there are multiple species, it may be that they have different ecological requirements, and therefore different approaches to their conservation are needed.” Cryer says. “This study further reinforces the power of DNA barcoding for rapid, preliminary species identification. Especially in the tropics, where habitat loss, climate change and infectious disease continually threaten many undescribed amphibian species.”

Japanese scientists have identified the molecular mechanism that gives the skin secretions of a species of frog effective antimicrobial properties. Unraveling the molecular mechanism that facilitates antimicrobial activity of these peptides can help us better understand how the defense system of the frog has evolved, and how this can be used to fight microbial infections of medical importance: here.

How amphibians became better parents than fish


This 2014 video says about itself:

Bullfrog Dad Protects His Tadpoles

The African bullfrog (Pyxicephalus adspersus) is the biggest frog in Africa and very aggressive. But in spite of that, it’s a devoted father. Bullfrogs spawn in little pools around the margins of larger ponds and after mating is over one male stays to keep watch over the newly hatched tadpoles. If the pool begins to dry up the dutiful dad digs a channel to a new water source.

From the University of Bath in England:

Evolution from water to land led to better parenting

April 10, 2019

The evolution of aquatic creatures to start living on land made them into more attentive parents, says new research on frogs led by the Milner Centre for Evolution at the University of Bath.

A study by an international team of researchers, published in Proceedings of the Royal Society of London B, looked at the parental care of over 1000 species of frogs and toads, and found those that reproduced on land invested more time and effort looking after their offspring.

The authors suggest that because parental care increases the rate of survival of their young, it has played a key role in the colonisation of terrestrial habitats, not only for amphibians but also early tetrapods which ultimately gave rise to mammals including humans.

The parenting behaviour of frogs and toads is very diverse, with care ranging from constructing a foam nest or attending the eggs, to more elaborate forms such as internal brooding of offspring or cooperation between parents to protect and provide food for their young.

Some frogs that lay their eggs on land protect them from drying out by urinating on them. Others brood their eggs in their stomach or look after their eggs or hatched tadpoles by carrying them on their backs.

Parental care may last for weeks whilst the parents defend, nurture and nourish their developing young. There are even frogs that skip the tadpole stage to give birth their babies as fully developed froglets that are readily capable of independent life.

Dr Balázs Vági, from University of Debrecen (Hungary), first author of the paper said:

“Most people think about amphibians as an ancient group with simple social behaviours which need an aquatic habitat for its reproduction.

“In fact, none of these are true in general. Most of the diversity of modern amphibians (8000 species, of which 7000 are frogs and toads) evolved after the cataclysm that wiped out the dinosaurs.

“And they have striking adaptations to gain independence from water. Amphibian eggs and larvae are sensitive to drying out and are a favourable prey for many predators. But parents have invented different strategies to defend them, and to nourish offspring in nutrient-scarce habitats.

“Protection was evolved many times both in male and female frogs, while nourishing is predominantly, but not exclusively, a task for the mother. The complex forms of caring co-evolved with sophisticated breeding systems, including cooperation in care and tenacious pair bonds in the most extreme cases.”

Professor Tamás Székely, Royal Society Wolfson Merit Award holder from the Milner Centre for Evolution at the University of Bath, said: “Frogs and toads exhibit some of the most spectacular variation in parenting across all vertebrates, although the origin and maintenance of this variation have been a puzzle.

“Using the most detailed phylogenetic analyses of parenting in any taxa, we discovered that parenting relates to their ecology and life history.

“Thus complex social behaviour such as parenting seems to allow frogs and toads to invade apparently unsuitable habitats such as deserts.

“However, the spectacular variation exhibited by frogs and toads unfortunately is under an unprecedented threat by diseases, habitat loss and illegal trade of endangered species.”

The study found that frogs that laid larger eggs tended to care for and protect their eggs for longer. They also found that in species where males were larger compared to females, the fathers were more attentive than those species where males are substantially smaller than their mate.

The findings suggest that parenting by males and females has co-evolved and that complex parenting traits have evolved several times in frogs and toads in response to breeding in terrestrial environments.

The researchers propose that tetrapods, four-legged animals, may have evolved complex parenting behaviour in a similar way when they moved from living in water to colonise the land.

The study also highlights the need for more work on frogs and toads. Amphibians (frogs, toads and allies) are among the most endangered vertebrates. By pulling together a vast amount of data on reproductive modes, life styles and ecology, the study will assist conservation efforts by making these data publicly available.

Seychelles frogs, new research


Metamorph Sooglossus sechellensis balanced on a 10 pence coin. Credit: Dr. Jim Labisko

From the University of Kent in England:

Conservationists discover hidden diversity in ancient frog family

April 11, 2019

Research scientists led by the University of Kent have uncovered hidden diversity within a type of frog found only in the Seychelles, showing that those on each island have their own distinct lineage.

The family tree of sooglossid frogs dates back at least 63 million years. They are living ancestors of those frogs that survived the meteor strike on earth approximately 66 million years ago, and their most recent common ancestor dates back some 63 million years, making them a highly evolutionarily distinct group.

However, recent work on their genetics led by Dr Jim Labisko from Kent’s School of Anthropology and Conversation revealed that until they can complete further investigations into their evolutionary relationships and verify the degree of differentiation between each island population, each island lineage needs to be considered as a potential new species, known as an Evolutionarily Significant Unit (ESU). As a result, Dr Labisko advises conservation managers they should do likewise and consider each as an ESU.

There are just four species of sooglossid frog; the Seychelles frog (Sooglossus sechellensis), Thomasset’s rock frog (So. thomasseti), Gardiner’s Seychelles frog (Sechellophryne gardineri) and the Seychelles palm frog (Se. pipilodryas).

Of the currently recognised sooglossid species, two (So. thomasseti and Se. pipilodryas) have been assessed as Critically Endangered, and two (So. sechellensis and Se. gardineri) as Endangered for the International Union for Conservation of Nature IUCN Red List. All four species are in the top 50 of ZSL’s (Zoological Society of London) Evolutionarily Distinct Globally Endangered (EDGE) amphibians.

Given the Red List and EDGE status of these unique frogs Dr Labisko and his colleagues are carrying out intensive monitoring to assess the level of risk from both climate change and disease to the endemic amphibians of the Seychelles.

Dr Labisko, who completed his PhD on sooglossid frogs at Kent’s Durrell Institute of Conservation and Ecology in 2016 said many of these frogs are so small and good at hiding the only way to observe them is by listening for their calls. Although tiny, the sound they emit can be around 100 decibels, equivalent to the sound volume of a power lawnmower.

Dr Labisko’s team are using sound monitors to record the vocal activity of sooglossid frogs for five minutes every hour, every day of the year, in combination with dataloggers that are sampling temperature and moisture conditions on an hourly basis

Dr Labisko said: ‘Amphibians play a vital role in the ecosystem as predators, munching on invertebrates like mites and mosquitos, so they contribute to keeping diseases like malaria and dengue in check. Losing them will have serious implications for human health.’

As a result of this study into the frogs, the research team will also contribute to regional investigations into climate change, making a local impact in the Seychelles.

Amphibians around the world are threatened by a lethal fungus known as chytrid. The monitoring of these sooglossid frogs will provide crucial data on amphibian behaviour in relation to climate and disease. If frogs are suddenly not heard in an area where they were previously, this could indicate a range-shift in response to warming temperatures, or the arrival of disease such as chytrid — the Seychelles is one of only two global regions of amphibian diversity where the disease is yet to be detected.

It may also impact on a variety of other endemic Seychelles flora and fauna, including the caecilians, a legless burrowing amphibian that is even more difficult to study than the elusive sooglossids.

Researchers know that caecilians can be found in similar habitats to the frogs, so they can use the frog activity and environmental data they are collecting to infer caecilian presence or absence and generate appropriate conservation strategies as a result.

Endemic, endangered and evolutionarily significant: cryptic lineages in Seychelles’ frogs (Anura: Sooglossidae) by Jim Labisko Richard A Griffiths Lindsay Chong-Seng Nancy Bunbury Simon T Maddock Kay S Bradfield Michelle L Taylor Jim J Groombridge is published in the Biological Journal of the Linnean Society.

Toxic but beautiful United States newts


This 5 April 2019 video says about itself:

On this episode of Breaking Trail: Legacy Series, we take a look back at the time Coyote and the crew caught a handful of TOXIC newts.. which also happen to be very adorable! On top of being adorable, these newts just so happen to be one of the most toxic in all of the US!

Breaking Trail leaves the map behind and follows adventurer and animal expert Coyote Peterson and his crew as they encounter a variety of wildlife in the most amazing environments on the planet!

Splendid leaf frog in Costa Rica, video


This 31 March 2019 video says about itself:

On this episode of Breaking Trail, the Brave Crew is in location in Costa Rica, and they FINALLY find a very special frog… the Splendid Leaf Frog! This is one RARE frog!

Get ready, you’re about to meet a rare frog that leaps back!

Breaking Trail leaves the map behind and follows adventurer and animal expert Coyote Peterson and his crew as they encounter a variety of wildlife in the most amazing environments on the planet!