Camuflaje sublime

Camuflaje sublime

Es sorprendente como algunos insectos para pasar desapercibidos sacrifican movilidad, agilidad, fortaleza, velocidad etc.

A mí me hacen preguntarme si les merece la pena ese “sacrificio” o por el contrario es la razón por la que existen.

Tu que crees?



 

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Que CALLADITO se lo tenían…

Es un pez si, si un pez, léelo y escúchalo.

El acto físico de la reproducción puede ser un asunto ruidoso para muchos animales, pero para la corvina del Golfo (Cynoscion othonopterus), es francamente ensordecedor. Cada primavera, millones de peces grises del tamaño de un tabla de snowboard emigran al delta del río Colorado y sincronizan su desove con las mareas y las fases de la luna. La agregación puede abarcar decenas de kilómetros, y los científicos creen que los grillos o ranas, como las corvinas, hacen ruido para comunicarse con parejas potenciales. En el transcurso de 4 días en la primavera de 2014, los investigadores usaron micrófonos de sonda y submarinos para registrar dónde estaban los peces y los sonidos que estaban haciendo. En el momento más ruidoso, los instrumentos registraron el coro en más de 150 decibelios, informa hoy el equipo en Biology Letters. Eso hace que el sonido sea el más fuerte jamás registrado para un pez, y uno de los sonidos más fuertes jamás capturados bajo el agua. El clic colectivo es tan ruidoso, de hecho, que los investigadores dicen que podría dañar el oído de otros animales marinos como las focas y las ballenas. Afortunadamente, solo ocurre una vez al año.

Traducido de la revista SCIENCEMAG.ORG



 

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Super termitas en Florida. (Inglés)

Florida Scientists Discover Super Termites, and They’re Not Genetically Modified

A hybrid colony of Coptotermes termites. A king C. gestroi (nutty-brown abdomen) is shown on the left, and a queen C. formosanus (orange abdomen) on the right. They are surrounded by their hybrid offspring, including eggs, larvae, workers, and soldiers. Photo by Thomas Chouvenc, University of Florida /IFAS. Larger photo.

By Richard LevineFormosan subterranean termites (Coptotermes formosanus) and Asian subterranean termites (Coptotermes gestroi) are the most damaging pest species in the world. Both are highly invasive and have spread throughout many areas of the world due to human activity, and their distributions overlap in some areas.

Now scientists in Florida have observed Formosan males mating with Asian females — in fact, they seem to prefer the Asian females more than females from their own species — and their hybrid offspring seem to grow colonies twice as fast as their parents. Their findings are published in the journal PLOS ONE, and are described in the following video:

Many hybrids are unable to reproduce (the mule, for example, which is the sterile hybrid offspring of a male donkey and a female horse). And many hybrids that actually can reproduce tend to lose vigor after one or more generations, which is why farmers often buy new hybrid seeds each growing season.

Richard Levine

But so far that doesn’t seem to be the case for these termite hybrids. In the laboratory, the Florida researchers are raising a hybrid colony that is growing twice as fast as same-species colonies, suggesting a potential case of hybrid vigor.

“Our hybrid colony is still showing high vigor, can potentially live up to 20 years, and can still cause a significant amount of damage,” said Dr. Thomas Chouvenc, a co-author from the UFL’s Ft. Lauderdale Research and Education Center.

While these laboratory observations remain to be confirmed in the field, the results still raise a tangible concern about the hybridization of these incredibly destructive pests, which could have significant economic impacts, according to the authors.

To get an idea of how potentially destructive they could be, watch this video of University of Florida researchers observing both termite species swarming simultaneously, including some shots of inter-species boot-knocking:

Don’t Panic … Yet … At least not too much

Right now we’ve got a vigorous hybrid colony in the lab, and we know that in the field both species swarm at the same time, which is when termites look for mates. However, we’ll have to wait and see whether the hybrids actually become established outside of the lab, and whether they can produce multiple generations.

“If our hybrid colony matures in 5-6 years, it MAY produce reproductives,” Dr. Chouvenc said. “This remains a mystery so far, because it’s too early for us to observe. The fertility of the reproductives will determine whether the hybrid is a ‘mule’ or not. If the hybrid vigor and viability that we observed in workers and soldiers also apply to the reproductives, then we will have introgression. If not, they will be sterile, with no chance of gene transfer from one population to the other.”

However, even if they do not produce viable reproductives, the hybrids could still be problematic in the wild. A C. formosanus colony can grow to contain millions of individuals within five to eight years, and since the hybrid colony in the UFL lab is growing at least as fast as its parental species, it’s reasonable to assume that hybrid colonies will also contain millions of termites after five years or so.

“Even if they don’t produce reproductives, you still have a million mouths to feed, and the colonies can be extremely long lived,” Dr. Chouvenc said.

“What we are dealing with here is a termite colony that acts like a super organism,” said Dr. Nan-Yao Su, another UFL professor and co-author of the study. “Whether or not it produces reproductives, the colony itself poses a serious threat to a homeowner.”

UPDATE (March 27, 2015): The following video features Dr. Chouvenc describing their discovery in his own words. He and his UFL colleagues encourage Florida residents to send them termite specimens if they see swarms so they can be identified and mapped:

🐜🐜🐜

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