Frogs re-evolved lost teeth

"Frogs re-evolved 'lost' bottom teeth after more than 200 million years, according to new research. Tree-dwelling Gastrotheca guentheri are the only frogs with teeth on both their upper and lower jaw. The reappearance of these lower teeth after such a long time fuels debate about whether complex traits are lost in evolution or if they can resurface. Scientists suggest this new evidence identifies a 'loophole' in previous theories."

BBC - Frogs re-evolved lost lower teeth

Cuban Frogs Hitched Rides to Florida

Two species of invasive frog which are hopping their way through Florida probably got to the state by hitching a ride on floating debris from Cuba. Amphibian experts have long wrangled over the origins of the greenhouse frog (Eleutherodactylus planirostris) and the Cuban treefrog (Osteopilus septentrionalis). The two species are widespread across the Caribbean, but were first spotted in the Florida Keys - the island chain that starts at Florida's southeastern tip - in the mid-1800s. A hundred years later, both began to be firmly established on the mainland and embarked on a relentless advance.

Cuban Frogs Hitched Rides to Florida: Discovery News

A long time

A long time ago, I made a new year resolution. It's taken a long time, but I've kept it. I maintain quite a few less species than I did at the start of 2009. Yesterday, the last to go were my Typhlonectes natans.

I'll miss them.

The Effects Of Climate Change Wildlife And Terrestrial Ecosystems

Climate change and biodiversity are interconnected. Unsustainable human activities that increase accumulation of greenhouse gases and hinder the natural balance of atmospheric greenhouse gases aggravate the effects of climate change on biodiversity. Rising seas-levels could inundate coastal habitats and stem the flow of nutrients from the ocean to the terrestrial ecosystems. Altered climate regimes directly affect wildlife, their behavior, migration, foraging, growth and reproduction. Climate change could disturb the dynamic equilibrium of terrestrial ecosystems by affecting ecosystem productivity, biomass production, hydrological balance, and trophic interactions. Further, climate change intensifies natural disasters and shifts in natural disturbance regimes. Such processes impose physiological and environmental stress on terrestrial ecosystems which adversely affect the ecosystem resistance and resilience. Moreover, warming atmosphere causes thermal optima to shift towards high latitudes and high altitudes. Terrestrial biota readily responds to temperature, where both flora and fauna alter distributions toward more favorable climatic conditions. Some climatic parameters that drive life history events, such as photoperiod, are fixed, while others, such as the timing of spring weather, are changing because of greenhouse gasses. The resulting mismatch between fixed and variable drivers of phenology, such as in mating, breeding, migration, hibernation, and post-hibernation activities, will disadvantage some species and benefit others. This will result in new ecosystems. Warming temperature favors biological activities of wildlife pathogens, since high temperature increases breeding rate, survival, hatching success and transmission of wildlife parasites and disease-causing agents. Climate change dissociates species interactions, mutual associations and a multitude of ecosystem functions. Ultimately, climate change predisposes native terrestrial wildlife to extinction and alters the functions and structure of terrestrial ecosystems. Biodiversity provides ecosystem services including the regulation and mitigation of the adverse impacts of climate change. Therefore, biodiversity conservation and terrestrial ecosystem management is critical to address climate change. Robust climate-oriented models with the use of GIS and remote sensing technology are needed to make effective predictions about the spatial and temporal effects of climate change.

The Effects Of Climate Change On Global Wildlife And Terrestrial Ecosystems. (2010) Taprobanica ISSN 1800-427X 2(1) 30-47

Sunbathing tadpoles make easy prey

A small increase in exposure to ultraviolet light from the sun — similar to that caused by thinning of the ozone layer that guards Earth from radiation — can have a detrimental effect on tadpoles.

Medium-wavelength ultraviolet radiation, known as ultraviolet-B (UVB), makes tadpoles easier for predators to catch, suggesting that depletion of the ozone layer caused by humans releasing chemicals into the atmosphere could be contributing to declines in the populations of the world's amphibian species.

The study notes that reduced survival time in a predator environment was the only effect observed from the increased UVB exposure. UVB stress might be expected to cause changes in hatching time of embryos, hatching success, size, shape and 'burst swimming performance' (ability to sprint) for tadpoles, but these responses were not observed. The study suggests that it may be time to expand the typical suite of measured UVB responses.

Sunbathing tadpoles make easy prey: Nature News

How old is the olm?

The blind cave-adapted salamander Proteus anguinus has a very long lifespan – possibly as long as a century – apparently without evidence of age-related deterioration. Also known as the 'olm' or 'human fish', a breeding population of P. anguinus was protected in a cave in south-western France near Moulis, which is better known for its ancient churches and vintage Haut-Médoc. For nearly 60 years, this population has thrived in its leisurely way, maturing at about age 15 years and ovipositing about every 12.5 years, with an annual adult mortality of 1.6% which did not appear to increase after age 40. The oldest age documented in the population was 48, but some collected while immature are probably about 58.

There is no hint of accelerating mortality in adults that would indicate senescence. Extrapolating from this unchanging mortality up to about age 50, the authors estimate a life expectancy at age 6 for the olm of 68.5 years. Voituron and colleagues used the ratio between life expectancy and maximum recorded longevity in other species to estimate a 100 year maximum lifespan for a population of 400 animals. This estimated maximum lifespan of a 15–20 g adult surpasses the predicted longevity of other amphibians based on allometric equations correcting for body mass. The giant salamanders of China and Japan (Andrias davidianus and A. japonicus) which weigh 25–60 kg, 1,000-fold more than the olm, are also reputed to live more than 50 years, however, there is no Andrias population for which adult mortality statistics can be calculated. Evidently, under protected conditions, gigantism is not needed for great longevity. It would not be surprising if some frogs could survive at least as long as the salamanders, big and small. Unfortunately, no adult population has been established for adult longevity and we are left with a few reports from zoos that some frogs and toads can live beyond 30 years.


Blind cave salamanders age very slowly: A new member of Methuselah's Bestiary. (2011) BioEssays 33(1): 1521-1878 doi 10.1002/bies.201000111

Frogs iinnnn spaaaaaaace!!!

“Amphibians possess the ability to vomit in response to a variety of stimuli that provoke emesis [vomiting] in mammals. Pharmacological studies have establish that the ejection of gastric contents and the basic mechanism for vomiting have been phylogenetically conserved among these tetrapods. As part of on-going comparative studies on emesis in vertebrates, we previously documented that some postmetamorphic anurans and salamander larvae experience motion-induced emesis when exposed to the provocative stimulus of parabolic aircraft flight. However, more recent experiments suggest that there are strict conditions for inducing emesis in amphibians exposed to parabolic flight and that amphibians are not as sensitive to this stimulus as mammals. Further studies on emesis in lower vertebrates may help us understand the processes that cause emesis in abnormal gravitational regimes.”

Frog barf iinnnn spaaaaaaace!!! | Discover Magazine: Emesis and space motion sickness in amphibians.