The Weirdness of NATURE

Spiders spend a lot of time crafting their webs in hopes of making a meal out of all manner of winged insect--but a recently discovered species of wasp is found to use the spider's engineering prowess to it's own advantage. Through a not yet understood chemical process, the wasps are able to, quite literally, enslave the unsuspecting spiders to build a nest for their larva, and after all that hard work, become their first meal. Sure, it seems pretty dastardly, but researchers say it's evolution.

According to a study published by a Brazilian team in the Journal of Natural History, and reported by Correio Braziliense, the newly discovered wasp species, a member of the Hymenoptera family, is able to control some spiders through a chemical process that remains a mystery.

How the Wasp Enslaves the Spider
A female wasp will target a spider and immobilize it with an unknown venom injected into its mouth--at which point the wasp lays its eggs on the spider's abdomen. When the spider revives, it seems to carry on unaffected as the wasp larvae develop.

Over the course of several days, as the larvae grows riding on the spider's body, it releases a chemical that changes the behavior of its host. Instead of its normally orderly web-pattern construction, the spider begins to build a special cocoon for the larvae--controlled by the mysterious substance they emit. According to researchers:

It may be a neurotransmitter or a potential neurotoxin that alters the behavior of the spider in building the web. This is because the spider is weaving a structure of three to four spokes and a central part of the cocoon where it will be.

A normal web, left, compared to one built by an enslaved spider, right.

Spiders Build Tough Wasp Homes
The cocoon is thought to be an ideal wasp nursery because "apparently, the structure is much more resistant to the weight of the cocoon and climatic factors such as rain."

As the wasps mature inside their custom-built home, they draw nutrients from the spider who constructed it--eventually devouring it completely when fully developed. So much for gratitude.

An Evolutionary Advantage?
While it seems like a pretty one-sided deal, scientists are hoping to better understand the evolutionary advantage of the wasp and spider relationship. According to researchers involved in the study, the behavioral change induced by the wasp may lead to new research into other species where similar influences have been observed.

Scientists also suspect that the chemicals used by the wasp may have some practical application.

The aim is to unravel this mystery in future experiments. We know it's possible to have medicinal properties in this substance, because the compound is shown to be very strong.

Let's hope that the wasp's special enslaving chemical doesn't fall into the wrong hands, however--one day they're terrorizing our picnics, the next we could be building their houses.

Here's something weird.......my dog found a cricket and jumped on it and guess what crawled out of it's smashed body. A long, skinny worm! What kind of relationship is that, a worm in a cricket! Parasites all over I tell ya!

Parasites all over I tell ya!

WASHINGTON (Reuters) – Atrazine, one of the most commonly used and controversial weedkillers, can turn male frogs into females, researchers reported on Monday.

The experiment is the first to show such complete effects of atrazine, which had been known to disrupt hormones and which is one of the chief suspects in the decline of amphibians such as frogs around the world.

"Atrazine-exposed males were both demasculinized (chemically castrated) and completely feminized as adults," Tyrone Hayes of the University of California Berkeley and colleagues wrote in the Proceedings of the National Academy of Sciences.

The chemical had been shown to disrupt development and make frogs develop both male and female features -- termed hermaphroditism. This study of 40 male frogs shows the process can go even further, Hayes said.

"Before, we knew we got fewer males than we should have, and we got hermaphrodites. Now, we have clearly shown that many of these animals are sex-reversed males," Hayes said in a statement.

"Atrazine has caused a hormonal imbalance that has made them develop into the wrong sex, in terms of their genetic constitution."

SIMILAR EFFECTS ON HUMANS?

Whether the effects translate to humans is far from clear. Frogs have thin skin that can absorb chemicals easily and they literally bathe in the polluted water.

The European Union banned atrazine in 2004. The finding may add pressure to the United States to more closely regulate the chemical, used widely in agriculture.

"Approximately 80 million pounds (36,287 tonnes) are applied annually in the United States alone, and atrazine is the most common pesticide contaminant of ground and surface water," the researchers wrote.

"Atrazine can be transported more than 1,000 km (621 miles) from the point of application via rainfall and, as a result, contaminates otherwise pristine habitats, even in remote areas where it is not used," they added, citing other researchers.

"In fact, more than a half million pounds (227 tonnes) of atrazine are precipitated in rainfall each year in the United States."

The U.S. Environmental Protection Agency said in October it was reviewing the health impacts of atrazine.

Syngenta AG, one of several companies that makes atrazine, has long defended its safety. The company says it is one of the best-studied herbicides available and pointed to prior safety reviews from the EPA and World Health Organization, among others.

Hayes and colleagues studied 40 African clawed frogs, keeping them in water contaminated with 2.5 ppb (parts per billion) of atrazine. The EPA's current drinking water standard is 3 ppb.

"Ten percent of the exposed genetic males developed into functional females that copulated with unexposed males and produced viable eggs," the researchers wrote.

"Regardless of the mechanism, the impacts of atrazine on amphibians and on wildlife in general are potentially devastating," they wrote.

"The negative impacts on wild amphibians is especially concerning given that the dose examined here (2.5 ppb) is in the range that animals experience year-round in areas where atrazine is used as well within levels found in rainfall, in which levels can exceed 100 ppb in the Midwestern United States," they added.

The giggling sounds of a hyena contain important information about the animal's status, say scientists.

In the first study to decipher the hyena's so-called "laugh", they have shown that the pitch of the giggle reveals a hyena's age.

What is more, variations in the frequency of notes used when a hyena makes a noise convey information about the animal's social rank.

Details of the US-based research are published in the journal BMC Ecology.

Professor Frederic Theunissen from the University of California at Berkeley, US, and Professor Nicolas Mathevon from the Universite Jean Monnet in St Etienne, France, worked with a team of researchers to study 26 captive spotted hyenas held at a field station at Berkeley.

There they recorded the animals' calls in various social interactions, such as when the hyenas bickered over food, and established which elements of each call corresponded to other factors.

Last year, the researchers published some provisional results from the study.

Now they have confirmed that the pitch of the giggle reveals a hyena's age, while variations in the frequency of notes can encode information about dominant and subordinate status.

"The hyena's laugh gives receivers cues to assess the social rank of the emitting individual," says Professor Theunissen.

"This may allow hyenas to establish feeding rights and organise their food-gathering activities."



Spotted hyenas (Crocuta crocuta) are mainly nocturnal, living in clans of between 10 and 90 individuals.

Hyena mother with cub (Kate Shaw)
Spotted hyenas make up to 10 different types of vocalisation
"Whoops", with long inter-whoop intervals, are primarily used to signal that two individuals have become separated
"Grunts" or "soft growls" are emitted when hyenas of the same clan come into close contact

Often they hunt cooperatively, but this can generate intense competition as clan mates converge on a kill, fighting over its carcass.

However, among spotted hyenas, females dominate, holding a higher rank than all other males, whatever their age.

Profs Theunissen and Mathevon's research suggests that the animals convey this status via their laugh or giggle, which they usually make while fighting over food.

Previously their sounds had been considered a simple gesture of submission, but the new study has allowed researchers to identify exactly which individual hyena makes each giggle, and the circumstances in which they do so.

The information contained within the giggles could be especially important for males new to a clan, as they go immediately to the bottom of the hierarchy when they arrive.

Getting to know quickly who is who may give these individuals a better chance of improving their own status.

Giggles could also allow hyenas to recruit allies, for instance when one or two hyenas are outnumbered by lions fighting over the same kill.

Symbionts
There are many species of bacteria and other microorganisms that live on or inside the healthy human body. In fact, 90% of the cells in (or on) a human body are microbes, by number (much less by mass or volume).[3] Some of these symbionts are necessary for our health. Those that neither help nor harm us are called commensal organisms. Besides these, there are harmful parasites and pathogens

Churchpeople?

Adults have short, flexible antennae, large compound eyes and three ocelli. In most species, the males' eyes are large and the front legs unusually long, for use in locating and grasping females during mid-air mating. In some species, all legs aside from the males' front legs are useless. Uniquely among insects, mayflies possess paired genitalia, with the male having two penises and the female two gonopores. The abdomen is roughly cylindrical, with ten segments and two long cerci at the tip.