From the Smithsonian Tropical Research Institute what seems like a repeat claim. Readers may recall that climate change was once before blamed for frog mortality and mutation only to discover through later research it wasn’t connected at all.
Climate change may alter amphibian evolution
Most of the more than 6,000 species of frogs in the world lay their eggs in water. But many tropical frogs lay their eggs out of water. This behavior protects the eggs from aquatic predators, such as fish and tadpoles, but also increases their risk of drying out. Justin Touchon, post-doctoral fellow at the Smithsonian Tropical Research Institute, discovered that climate change in Panama may be altering frogs’ course of evolution.
By analyzing long-term rainfall data collected by the Panama Canal Authority, Touchon discovered that rainfall patterns are changing just as climate-change models predict.
“Over the past four decades, rainfall has become more sporadic during the wet season,” said Touchon. “The number of rainy days decreased, and the number of gaps between storms increased.”
The eggs of the pantless treefrog, Dendropsophus ebraccatus, are extremely susceptible to drying. The embryos die within a day when there is no rain. Heavy rains trigger breeding, so as storms become sporadic, the chance of rain within a day of being laid decrease and so does egg survival.
As weather patterns have changed, the advantage of laying eggs out of water has decreased, not only for pantless treefrogs but potentially for many species. “Pantless treefrogs can switch between laying eggs in water or on leaves, so they may weather the changes we are seeing in rainfall better than other species that have lost the ability to lay eggs in water,” said Touchon. “Being flexible in where they put their eggs gives them more options and allows them to make decisions in a given habitat that will increase the survival of their offspring.”
The Smithsonian Tropical Research Institute, headquartered in Panama City, Panama, is a unit of the Smithsonian Institution. The Institute furthers the understanding of tropical nature and its importance to human welfare, trains students to conduct research in the tropics and promotes conservation by increasing public awareness of the beauty and importance of tropical ecosystems. Website: www.stri.si.edu.
Touchon J.C. 2012 A treefrog with reproductive mode plasticity reveals a changing balance of selection for non-aquatic egg-laying. The American Naturalist, online: doi:10.5061/dryad.8j1hb
For those wondering about geological epochs, here is a good overview:
http://www.climate4you.com/images/GeologicalTimeScale.gif
Wikipedia has has their “Late Jurassic” and “Early Jurassic” epochs grammatically wrong (back to front) to what I was explaining, 150.8 ± 4.0 – 145.5 ± 4.0 Mya (Million Years Ago) is earlier than 199.6 ± 0.6 – 196.5 ± 1.0 Mya (Million Years Ago).
To go with my geological chart above:
http://omniclimate.files.wordpress.com/2011/12/28392301.jpg
@ur momisugly D Böehm
Nice chart.
I was explaining the above using the timeline correctly from the present to the past i.e. Present —> Early in the past —> later in the past with the term “Million years ago” whereas other sources explain it from a point in the past to the present but use term “Million years ago”. Maybe I’m wrong but being meticulous/pedantic helps to gain a better understanding.
stephen richards;
You don’t gots a right and proper frog’s name. Please rectify, so as not to further confuse the befuddled. Or vice versa.
Have the hot, panting frogs changed behaviour as to where they choose to lay their eggs? What fraction led to successful procreation? We are not told because, from the abstract, the questions appear not to have even been asked.
So, umm, what was the question again?
Eggs laid out of water will dry out, if it doesn’t rain. Yeah, some did! Check.
Eggs laid in water might get eaten. Yeah, some did! Check.
Next project: If it rains too much, will the fish flounder up out of the water and eat the eggs that were laid on land? Who knows? Cute frogs, though.
It has recently been verified that frogs are reacting strongly to anthropogenic global warming by “plunking their magic twangers.” This act seems to provide them both satisfaction and protection, although it is common only among frogs over 50 years old. Rumors that there is a sexually questionable warmist researcher named Buffalo Bob or Bill or somesuch who derives pleasure from titillating these frogs are unfounded and possibly libelous. Please exercise care when discussing this subject in public fora.
Thank you.
H. D.
Local changes in rainfall affect amphibians behaviour and maybe even physiology over a few generations.
That sounds like a big finding in the 19th century but now, well, I’ll not bother researching more deeply. It sounds reasonable.
Yet another dopey bit of Goldilocks ‘research’. The climate conditions for these frogs were perfect and static in just the spot the researchers happened to pick, until SUVs were invented. Or something like that.
A lot of these frogspecies guard their eggs and wet them every other hour.
So what ‘s the problem?
I thought that’s what evolution was for….
I wish he would give an example of those frog species that have “lost the ability to lay eggs in water”. I suspect that those species already have other adaptations to mitigate drying of the eggs. Frogs that lay eggs on land have developed some amazing parental care behaviors.
Climate change may alter amphibian evolution
============
really, only “may”?
****
markopanama says:
October 25, 2012 at 11:21 am
Given that except for the three months or so of “dry season” it rains here virtually every day, 200-300 inches per year
****
I’d love to at least experience that kind of verdant rain-forest climate, but the endless humidity/sweating/wetness/mildew/fungi might wear one down. 🙂 Escaping to a higher elevation would doubtless help….
So? What’s new?
Temperature of egg incubation determines sex in Alligator – Naturewww.nature.com/nature/journal/v296/n5860/abs/296850a0.html
http://www.nature.com/nature/journal/v296/n5860/abs/296850a0.html
Messed up the link.
get those frogs some pants