Singin’ in the heat

9 03 2017
coqui & forest

Common coqui frog male (Eleutherodactylus coqui, snout-to vent length average ~ 3 cm) camouflaged in the fronds of an epiphyte in the El Yunque National Forest (Puerto Rico), along with an image of the enchanted forest of the Sierra de Luquillo where Narins & Meenderink did their study (4) – photos courtesy of Thomas Fletcher. This species can be found from sea level to the top of the highest peak in Puerto Rico (Cerro Punta = 1338 m). Native to mesic ecosystems, common coquis are well adapted to a terrestrial life, e.g., they lack interdigital webbing that support swimming propulsion in many amphibians, and youngsters hatch directly from the egg without transiting a tadpole stage. The IUCN catalogues the species as ‘Least Concern’ though alerts recent declines in high-altitude populations caused by chytrid fungus – lethal to amphibians at a planetary scale (9). Remarkably, the species has been introduced to Florida, Hawaii, the Dominican Republic and the Virgin Islands where it can become a pest due to high fertility rates (several >20 egg clutches/female/year).

Frog songs are species-specific and highly useful for the study of tropical communities, which host the highest amphibian diversities globally. The auditory system of females and the vocal system of males have co-evolved to facilitate reproductive encounters, but global warming might be disrupting the frequency of sound-based encounters in some species..

It is a rainy night, and Don (Gene Kelly) has just left his love, Kathy (Debbie Reynolds), at home, starting one of the most famous musical movie scenes ever: Singin’ in the rain 

Amphibians (see Amphibians for kids by National Geographic) also love to sing in rainy nights when males call for a partner, but now they have to do it in hotter conditions as local climates become warmer. Vocal behaviour is a critical trait in the life history of many frog species because it mediates recognition between individuals, including sexual selection by females (1).

With few exceptions, every species has a different and unique call, so scientists can use call features to identify species, and this trait is particularly useful in the inventory of diverse tropical communities (2). Differences in call frequency, duration and pitch, and in note, number, and repetition pattern, occur from one species to another. And even within species, songs can vary from individual to individual (as much as there are not two people with the same voice), and be tuned according to body size and environmental temperature (3). Read the rest of this entry »





To feed or to perish in an iceless world

1 02 2017
cb_climatechange2_polarbears_photo2

Emaciated female polar bear on drift ice in Hinlopen Strait (Svalbard, Norway), in July 2015 – courtesy of Kerstin Langenberger (www.arctic-dreams.com)

Evolution has designed polar bears to move, hunt and reproduce on a frozen and dynamic habitat that wanes and grows in thickness seasonally. But the modification of the annual cycle of Arctic ice due to global warming is triggering a trophic cascade, which already links polar bears to marine birds.

Popular and epicurean gastronomy claims that the best recipes should use seasonal veggies and fruits. Once upon a time, when there were no greenhouses, international trade routes, or as much frozen and canned food, our grandparents enjoyed what was available at the time. So in some years we had plenty of cherries, while during others we might have feasted on plums. Read the rest of this entry »





Where do citizens stand on climate change?

2 01 2017
Talk to the hand

Talk to the hand

Climate change caused by industrialisation is modifying the structure and function of the Biosphere. As we uncork 2017, our team launches a monthly section on plant and animal responses to modern climate change in the Spanish magazine Quercus – with an English version in Conservation Bytes. The initiative is the outreach component of a research project on the expression and evolution of heat-shock proteins at the thermal limits of Iberian lizards (papers in progress), supported by the British Ecological Society and the Spanish Ministry of Economy, Industry and Competitiveness. The series will feature key papers (linking climate change and biodiversity) that have been published in the primary literature throughout the last decade. To set the scene, we start off putting the emphasis on how people perceive climate change.

Salvador Herrando-Pérez, David R. Vieites & Miguel B. Araújo

“I would like to mention a cousin of mine, who is a Professor in Physics at the University of Seville – and asked about this matter [climate change], he stated: listen, I have gathered ten of the top scientists worldwide, and none has guaranteed what the weather will be like tomorrow in Seville, so how could anyone predict what is going to occur in the world 300 years ahead?”

Mariano Rajoy (Spanish President from 2011 to date) in a public speech on 22 October 2007

Weather (studied by meteorology) behaves like a chaotic system, so a little variation in the atmosphere can trigger large meteorological changes in the short term that are hard to predict. On the contrary, climate (studied by climatology) is a measure of average conditions in the long term and thus far more predictable than weather. There is less uncertainty in a climate prediction for the next century than in a weather prediction for the next month. The incorrect statement made by the Spanish President reflects harsh misinformation and/or lack of environment-related knowledge among our politicians.

Climate has changed consistently from the onset of the Industrial Revolution. The IPCC’s latest report stablishes with 95 to 100% certainty (solid evidence and high consensus given published research) that greenhouse gases from human activities are the main drivers of global warming since the second half of the 20th Century (1,2). The IPCC also flags that current concentrations of those gases have no parallel in the last 800,000 years, and that climate predictions for the 21st Century vary mostly according to how we manage our greenhouse emissions (1,3). Read the rest of this entry »





Cartoon guide to biodiversity loss XL

7 12 2016

That’s ’40’, of course. Six more biodiversity cartoons, and the last for 2016. See full stock of previous ‘Cartoon guide to biodiversity loss’ compendia here.

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Cartoon guide to biodiversity loss XXXIX

20 10 2016

Six more biodiversity cartoons coming to you all the way from Sweden (where I’ve been all week). See full stock of previous ‘Cartoon guide to biodiversity loss’ compendia here.

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Cartoon guide to biodiversity loss XXXVIII

25 08 2016

Another six biodiversity cartoons for your midday chuckle & groan. There’s even one in there that takes the mickey out of some of my own research (see if you can figure out which one). See full stock of previous ‘Cartoon guide to biodiversity loss’ compendia here.

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Cartoon guide to biodiversity loss XXXVII

18 05 2016

Another six biodiversity cartoons because I have a full-on month of lecturing. I’ll call this one the ‘over-population’ issue. See full stock of previous ‘Cartoon guide to biodiversity loss’ compendia here.

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