Chameleons!

May 6, 2010 by · Leave a Comment 

tufail

Chameleons (family Chamaeleonidae) are a distinctive and highly specialized clade of lizards. They are distinguished by their parrot-like zygodactylous feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, their swaying gait, the possession by many of a prehensile tail, crests or horns on their distinctively shaped heads, and the ability of some to change color. Uniquely adapted for climbing and visual hunting, the approximately 160 species of chameleon range from Africa, Madagascar, Spain and Portugal, across south Asia, to Sri Lanka, have been introduced to Hawaii, California and Florida, and are found in warm habitats that vary from rain forest to desert conditions.

Chameleons vary greatly in size and body structure, with maximum total length varying from 3.3 cm (1.3 in.) in Brookesia minima (one of the world’s smallest reptiles) to 68.5 cm (27 in.) in the male Furcifer oustaleti. Many have head or facial ornamentation, such as nasal protrusions, or horn-like projections in the case of Chamaeleo jacksonii, or large crests on top of their head, like Chamaeleo calyptratus. Many species are sexually dimorphic, and males are typically much more ornamented than the female chameleons.

Chameleon species have in common their foot structure, eyes, lack of ears, and tongues.

Their eyes are the most distinctive among the reptiles. The upper and lower eyelids are joined, with only a pinhole large enough for the pupil to see through. They can rotate and focus separately to observe two different objects simultaneously. It in effect gives them a full 360-degree arc of vision around their body. When prey is located, both eyes can be focused in the same direction, giving sharp stereoscopic vision and depth perception. They have very good eyesight for reptiles, letting them see small insects from a long (5-10 cm) distance.

They lack a vomeronasal organ. Also, like snakes, they do not have an outer or a middle ear. This suggests that chameleons might be deaf, although it should be noted that snakes can sense vibration using a bone called the quadrate. Furthermore, some or maybe all chameleons, can communicate via vibrations that travel through solid substrates such as branches.

Chameleons have very long tongues (sometimes longer than their own body length) which they are capable of rapidly extending out of the mouth.

Tongue structure

The tongue extends out faster than human eyes can follow, at around 26 body lengths per second. The tongue hits the prey in about 30 thousandths of a second.[4] The tongue of the chameleon is a complex arrangement of bone, muscle and sinew. At the base of the tongue there is a bone and this is shot forward giving the tongue the initial momentum it needs to reach the prey quickly. At the tip of the elastic tongue there is a muscular, club-like structure covered in thick mucus that forms a suction cup.[5] Once the tip sticks to a prey item, it is drawn quickly back into the mouth, where the chameleon’s strong jaws crush it and it is consumed. Ultraviolet light is part of the visible spectrum for chameleons.[6] Chameleons exposed to ultraviolet light show increased social behavior and activity levels, are more inclined to bask and feed and are also more likely to reproduce as it has a positive effect on the pineal gland

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Europe: Anti-Semitism Up, Islamophobia Down

December 17, 2009 by · Leave a Comment 

By Sarah Stricker, Ynetnews

Study on ‘group-focused enmity’ conducted by researchers from University of Bielefeld in Germany finds hatred of Muslims decreased over past year, while hatred of Jews and homosexuals growing. Poland defined as most racist country.

Right-wing parties are growing stronger in Europe, and Swiss citizens have even voted in favor of a ban on mosque minarets, yet the fear or hatred of Islam in the continent has dropped over the past year, according to a study conducted in Germany and published Sunday. However, hatred of Jews and homosexuals is on the rise.

For the last eight years, the Institute for Interdisciplinary Research on Conflict and Violence at the University of Bielefeld has been running an annual study called “German Conditions” to learn about “group focused enmity” such as xenophobia, sexism, racism, anti-Semitism, and prejudices against unemployed, disabled, homeless or homosexual people in Germany.

Due to the financial crisis and the fears of the future, poverty and unemployment that are being stoked by that, the researchers expected a rise this year.

But compared to last year’s results (as well as those of 2002), the level of resentment against most minorities declined – sexism and racism even considerably, Islamophobia slightly. There were only two exceptions: Homophobia and anti-Semitism.

Hatred of both groups is on the rise as they are considered to be found also among people of a high status.

Beate Küpper, one of the study’s main researchers, believes that the financial crisis may in fact be a possible explanation for that.

Küpper said that although in comparison to other European countries Germany was on average, it was staggering that in the light of German history, 48% still agreed with anti-Semitic statements.

For the first time, the study also compared xenophobia among European countries like Britain, France, Germany, the Netherlands, Italy, Portugal, Poland, and Hungary. According to their findings, the level of prejudices against minorities in Europe is alarming.

About 50.4% of the population agreed that “there are too many immigrants” in their country, 54.4% believe that “the Islam is a religion of intolerance.” Interestingly enough, the percentage of people who believe “that there are too many Muslims” in their country is especially high in those countries that actually have a low percentage of Muslims living in them.

Nearly one-third (31.3%) of the Europeans somewhat or strongly agree that “there is a natural hierarchy between black and white people”. A majority of 60.2% stick to traditional gender roles, demanding that “women should take their role as wives and mothers more seriously.” Some 42.6% deny equal value of gay men and lesbian women and judge homosexuality as “immoral”.

Hiding behind criticism of Israel

Anti-Semitism is also still widely spread in Europe. The team of scientists from the universities of Amsterdam, Bielefeld, Budapest, Grenoble, Lisbon, Marburg, Oxford, Padua, Paris, and Warsaw found that 41.2% of Europeans believe that “Jews try to take advantage of having been victims during the Nazi era”. The highest degree of affirmation was in Poland – 72%, and the lowest in the Netherlands – 5.6%.

One-quarter of Europeans (24.5%) believe that “Jews have too much influence”, and nearly one-third (31%) agree that “Jews in general do not care about anything or anyone but their own kind. On the other hand, 61.9% say that Jews “enrich our culture”, especially in the Netherlands, Britain and Germany.

They study also measured the degree of anti-Semitism hidden behind a specific criticism of Israel’s policy towards the Palestinians that uses anti-Semitic terms such as “war of persecution” and a generalization to “all Jews”.

Some 45.7% of the Europeans (apart for France, where this facet of anti-Semitism was not measured) somewhat or strongly agree that “Israel is conducting a war of extermination against the Palestinians.” About 37.4% agree with the following statement: “Considering Israel’s policy, I can understand why people do not like Jews.”

Overall, the level of anti-Semitic attitudes varies quite a lot across Europe with comparably lower levels of anti-Semitic attitudes in Britain and the Netherlands and significantly higher levels in Portugal, and especially Poland and Hungary.

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