Spider Attack Preserved in Amber
Researchers from Oregon State University (college of science) have discovered a remarkable fossil showing the moment when an orb spider approached its victim ensnared in its web. The fossil consists of the remains of the spider and a parasitic wasp, preserved in amber just as the spider was about to pounce upon the insect, as it was held fast by the silken threads of the spider's web. Amber is the hardened remains of sticky, often scented resin that is produced by certain types of trees as protection against damage to bark and in order to help protect against disease and fungal attacks. Insects and other organisms can become trapped in the sticky resin as it flows down the trunk or branches and when fossilised and preserved as amber, these organic remains can be studied by scientists. Trees first evolved the ability to produce resin of this nature in the Jurassic, but this piece of amber, discovered in the Hukawng Valley (also known as the Hukaung Valley), in northern Burma dates from the later Cretaceous geological period.
Famous Amber Fossil Site in Asia
The Hukaung Valley has been mined for amber and gold for many years, it has already produced a number of amber fossils containing insect remains. About ten years ago, the fossilised remains of the world's oldest bee was discovered in an amber nodule from a mine in the Hukaung Valley. However, this is the first discovery of a predator/prey interaction concerning a spider and an insect trapped in a web. The amber nodule containing the fossilised remains has been dated to approximately 97-100 million years ago (Albian faunal stage of the Cretaceous) - a time when the dinosaurs ruled the Earth.
Social Behaviour in Arachnids
In addition to the first spider, the silk and the remains of the spider's attempted meal, the wasp, the amber nodule also contained the remains of a second male spider. Scientists at the Oregon State University have interpreted this as evidence of social behaviour amongst arachnids. Most extant species of spider are solitary hunters, often they are cannibalistic towards their own kind, mature males and females will attack immature members of their own species. A number of species today show signs of social behaviour, living in colonies or aggregations. The Oregon based team postulate that this fossil is evidence of such social, colonial activity in spiders back in the Cretaceous, the first evidence found of tolerance of other members of their own species by a spider.
Professor Emeritus of Zoology at Oregon State University, George Poiner Junior, a recognised authority on invertebrate fossils stated that the juvenile spider was attempting to pounce on the trapped, tiny parasitic wasp, but it never quite reached it. Both animals were covered in the tree resin before the spider could reach its victim.
Amazing Amber Fossils Found
Over recent years, palaeontologists have discovered some amazing fossil specimens preserved in amber, from ancient Arthropods, to numerous types of insect, pollen, plant debris, even a frog, hairs from mammal and feathers from either an ancient bird or a dinosaur. Such fossils provide an insight into deep time, a micro world which helps scientists to understand more about ecosystems and habitats.
Wasp Being Attacked by Ancient Spider
The wasp has been identified as an ancestor of today's parasitic wasps that attack and disable spiders and insects and lay their own eggs into the paralysed body of their victim or instead, parasitise the eggs of such creatures. The kind of spider preserved in the amber, a relative of today's tropical orb spiders, but a member of an extinct genus would probably have been the sort of creature the wasp would have liked to attack. As the research team members have stated in their press conferences, this fossil preserves the moment when a spider was able to turn the tables on a parasitic wasp. There were at least fifteen silken threads preserved in the amber nodule, evidence of the spider's web. Some of these threads had trapped the wasp.
Article Source: http://EzineArticles.com/7324056
Technology has made its way into mainstream life and it is important to incorporate it into the classroom. Science in the classroom is introduced in elementary school and often technology is a tool that can be used to encourage the interest of the student in the subject matter. If the student can grasp the basics and develop an interest in science at an early age, studies show that the student will continue that interest throughout his school years. Adding technology to the classroom initially costs a great deal. However, the expense is worth it when compared to the positive outcome achieved.
One way to add technology in a science classroom is to use a liquid-crystal display (LCD) projector. This is a video projector that can display computer data on a screen or other flat surface. This technology takes the place of the overhead projector. Light from a lamp of metal-Halide is sent through Diachronic filters or prisms that separate the light. Three panels of red, green, and blue make up the video signal. The polarized light passes through these panels and each pixel can be opened or closed. The opening and closing of the pixels is what yields the range of colors found in the image that is projected. Some of the other technology available is digital light processing (DLP) or liquid crystal on silicon (LCOS) and are decreasing in cost so that they are becoming more affordable for classroom use.
The technology involved in the LCD allows the unit to be smaller and portable. In order to get the best resolution it is recommended that the projection surface be gray, white, or black. The color produced is a direct correlation to the quality surface and projector used. White is usually the choice for classroom user. The projector must be located at the correct distance from the projection surface and the ratio is usually found in the material that comes with the LCD. This technology was first invented by Gene Dolgoff in 1968, but it wasn't until 1984 that he put together the first projector. The technology later evolved into the high-definition television (HDTV).
The LCD projector can be used in the science classroom to project images onto the screen. This enables all the students to view the data of one computer. With a limited budget, the school is able to still integrate information from the computer for all the students, without having to supply each student with a computer. It is recommended that the teacher start with an informative, perhaps animated, video that will introduce the content to the student. This will capture the attention of the student and the student will retain more of the content when his interest is captured. The teacher can search the web for sites that offer free streaming or look to the curriculum for these tools.
Try to select a model for projection that will allow you to point and click and manipulate the projection. For example, if the module is on the content of the atom, then manipulating the screen can teach the student how atoms combine to form different substances. Dragging two hydrogen atoms to one oxygen atom would show the student the content of water. If a smart board is also connected to the LCD then the student can use a special pen to manipulate and the smart boards can give life to abstract concepts that enable a student to grasp the content. Experiments can also be done by manipulating the LCD images and this will help students participate in experiments that may not be available due to the high cost of separate lab stations and materials.
Researchers from Oregon State University (college of science) have discovered a remarkable fossil showing the moment when an orb spider approached its victim ensnared in its web. The fossil consists of the remains of the spider and a parasitic wasp, preserved in amber just as the spider was about to pounce upon the insect, as it was held fast by the silken threads of the spider's web. Amber is the hardened remains of sticky, often scented resin that is produced by certain types of trees as protection against damage to bark and in order to help protect against disease and fungal attacks. Insects and other organisms can become trapped in the sticky resin as it flows down the trunk or branches and when fossilised and preserved as amber, these organic remains can be studied by scientists. Trees first evolved the ability to produce resin of this nature in the Jurassic, but this piece of amber, discovered in the Hukawng Valley (also known as the Hukaung Valley), in northern Burma dates from the later Cretaceous geological period.
Famous Amber Fossil Site in Asia
The Hukaung Valley has been mined for amber and gold for many years, it has already produced a number of amber fossils containing insect remains. About ten years ago, the fossilised remains of the world's oldest bee was discovered in an amber nodule from a mine in the Hukaung Valley. However, this is the first discovery of a predator/prey interaction concerning a spider and an insect trapped in a web. The amber nodule containing the fossilised remains has been dated to approximately 97-100 million years ago (Albian faunal stage of the Cretaceous) - a time when the dinosaurs ruled the Earth.
Social Behaviour in Arachnids
In addition to the first spider, the silk and the remains of the spider's attempted meal, the wasp, the amber nodule also contained the remains of a second male spider. Scientists at the Oregon State University have interpreted this as evidence of social behaviour amongst arachnids. Most extant species of spider are solitary hunters, often they are cannibalistic towards their own kind, mature males and females will attack immature members of their own species. A number of species today show signs of social behaviour, living in colonies or aggregations. The Oregon based team postulate that this fossil is evidence of such social, colonial activity in spiders back in the Cretaceous, the first evidence found of tolerance of other members of their own species by a spider.
Professor Emeritus of Zoology at Oregon State University, George Poiner Junior, a recognised authority on invertebrate fossils stated that the juvenile spider was attempting to pounce on the trapped, tiny parasitic wasp, but it never quite reached it. Both animals were covered in the tree resin before the spider could reach its victim.
Amazing Amber Fossils Found
Over recent years, palaeontologists have discovered some amazing fossil specimens preserved in amber, from ancient Arthropods, to numerous types of insect, pollen, plant debris, even a frog, hairs from mammal and feathers from either an ancient bird or a dinosaur. Such fossils provide an insight into deep time, a micro world which helps scientists to understand more about ecosystems and habitats.
Wasp Being Attacked by Ancient Spider
The wasp has been identified as an ancestor of today's parasitic wasps that attack and disable spiders and insects and lay their own eggs into the paralysed body of their victim or instead, parasitise the eggs of such creatures. The kind of spider preserved in the amber, a relative of today's tropical orb spiders, but a member of an extinct genus would probably have been the sort of creature the wasp would have liked to attack. As the research team members have stated in their press conferences, this fossil preserves the moment when a spider was able to turn the tables on a parasitic wasp. There were at least fifteen silken threads preserved in the amber nodule, evidence of the spider's web. Some of these threads had trapped the wasp.
Article Source: http://EzineArticles.com/7324056
Technology has made its way into mainstream life and it is important to incorporate it into the classroom. Science in the classroom is introduced in elementary school and often technology is a tool that can be used to encourage the interest of the student in the subject matter. If the student can grasp the basics and develop an interest in science at an early age, studies show that the student will continue that interest throughout his school years. Adding technology to the classroom initially costs a great deal. However, the expense is worth it when compared to the positive outcome achieved.
One way to add technology in a science classroom is to use a liquid-crystal display (LCD) projector. This is a video projector that can display computer data on a screen or other flat surface. This technology takes the place of the overhead projector. Light from a lamp of metal-Halide is sent through Diachronic filters or prisms that separate the light. Three panels of red, green, and blue make up the video signal. The polarized light passes through these panels and each pixel can be opened or closed. The opening and closing of the pixels is what yields the range of colors found in the image that is projected. Some of the other technology available is digital light processing (DLP) or liquid crystal on silicon (LCOS) and are decreasing in cost so that they are becoming more affordable for classroom use.
The technology involved in the LCD allows the unit to be smaller and portable. In order to get the best resolution it is recommended that the projection surface be gray, white, or black. The color produced is a direct correlation to the quality surface and projector used. White is usually the choice for classroom user. The projector must be located at the correct distance from the projection surface and the ratio is usually found in the material that comes with the LCD. This technology was first invented by Gene Dolgoff in 1968, but it wasn't until 1984 that he put together the first projector. The technology later evolved into the high-definition television (HDTV).
The LCD projector can be used in the science classroom to project images onto the screen. This enables all the students to view the data of one computer. With a limited budget, the school is able to still integrate information from the computer for all the students, without having to supply each student with a computer. It is recommended that the teacher start with an informative, perhaps animated, video that will introduce the content to the student. This will capture the attention of the student and the student will retain more of the content when his interest is captured. The teacher can search the web for sites that offer free streaming or look to the curriculum for these tools.
Try to select a model for projection that will allow you to point and click and manipulate the projection. For example, if the module is on the content of the atom, then manipulating the screen can teach the student how atoms combine to form different substances. Dragging two hydrogen atoms to one oxygen atom would show the student the content of water. If a smart board is also connected to the LCD then the student can use a special pen to manipulate and the smart boards can give life to abstract concepts that enable a student to grasp the content. Experiments can also be done by manipulating the LCD images and this will help students participate in experiments that may not be available due to the high cost of separate lab stations and materials.
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