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12th January, 2014

A bitter feud between Edward Drinker Cope and Othniel Charles Marsh in the late 19th century truly built paleontology into the field it was today. It’s not clear what the starting point for their bitter rivalry was, but it only grew in intensity over the years. 
The two men were notorious for stealing fossils from each other’s dig sites by bribing workers, as well as destroying bones and writing scathing criticisms on each others published work in newspapers in an attempt to discredit one another.  These actions, among others, led to both suffering blows to their finances as well as their reputation in the field. 
Their obsessive battle for supremacy, however, led to the discovery of rich bone beds in the western United States. It also resulted in an increased interest in prehistoric life (both in the public forum and academia), leading to an increase in fossil hunting in the decades to come. 
Read more

A bitter feud between Edward Drinker Cope and Othniel Charles Marsh in the late 19th century truly built paleontology into the field it was today. It’s not clear what the starting point for their bitter rivalry was, but it only grew in intensity over the years. 

The two men were notorious for stealing fossils from each other’s dig sites by bribing workers, as well as destroying bones and writing scathing criticisms on each others published work in newspapers in an attempt to discredit one another.  These actions, among others, led to both suffering blows to their finances as well as their reputation in the field. 

Their obsessive battle for supremacy, however, led to the discovery of rich bone beds in the western United States. It also resulted in an increased interest in prehistoric life (both in the public forum and academia), leading to an increase in fossil hunting in the decades to come. 

Read more

12th January, 2014

Prehistoric Colors Preserved in Near-Perfect Beetle Fossils

BY BRANDON KEIM

Despite being tens of millions of years old, some beetle fossils appear almost as they did in life. Not only are their shape and structure preserved, but so are the actual colors of their shells, which have changed only slightly in the intervening eons.
Though relatively little-known, these fossils represent the purest of biological colors retrieved from deep time, far richer than much-celebrated pigment traces of dinosaur plumage and more varied than the hues of a few ancient plants.
In a study published Sept. 27 in Proceedings of the Royal Society B, researchers led by Yale University paleogeologist Maria McNamara analyzed 10 of these spectacular beetle fossils, ranging from 15 million to 47 million years old, which owe their enduring shades to the phenomenon of structural coloration. Unlike pigments, which generate color from light bouncing off a chemical, structural colors are produced by the interaction of light with nanometer-scale surface geometries.
Continue Reading Prehistoric Colors Preserved in Near-Perfect Beetle Fossils

BY BRANDON KEIM

Despite being tens of millions of years old, some beetle fossils appear almost as they did in life. Not only are their shape and structure preserved, but so are the actual colors of their shells, which have changed only slightly in the intervening eons.
Though relatively little-known, these fossils represent the purest of biological colors retrieved from deep time, far richer than much-celebrated pigment traces of dinosaur plumage and more varied than the hues of a few ancient plants.
In a study published Sept. 27 in Proceedings of the Royal Society B, researchers led by Yale University paleogeologist Maria McNamara analyzed 10 of these spectacular beetle fossils, ranging from 15 million to 47 million years old, which owe their enduring shades to the phenomenon of structural coloration. Unlike pigments, which generate color from light bouncing off a chemical, structural colors are produced by the interaction of light with nanometer-scale surface geometries.
Continue Reading

Prehistoric Colors Preserved in Near-Perfect Beetle Fossils

Despite being tens of millions of years old, some beetle fossils appear almost as they did in life. Not only are their shape and structure preserved, but so are the actual colors of their shells, which have changed only slightly in the intervening eons.

Though relatively little-known, these fossils represent the purest of biological colors retrieved from deep time, far richer than much-celebrated pigment traces of dinosaur plumage and more varied than the hues of a few ancient plants.

In a study published Sept. 27 in Proceedings of the Royal Society B, researchers led by Yale University paleogeologist Maria McNamara analyzed 10 of these spectacular beetle fossils, ranging from 15 million to 47 million years old, which owe their enduring shades to the phenomenon of structural coloration. Unlike pigments, which generate color from light bouncing off a chemical, structural colors are produced by the interaction of light with nanometer-scale surface geometries.

Continue Reading

12th January, 2014

A Brief Introduction

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Paleontology is the scientific study of prehistoric life. It includes the study of fossils to determine organisms’ evolution and interactions with each other and their environments (their paleoecology). Paleontological observations have been documented as far back as the 5th century BC. The science became established in the 18th century as a result of Georges Cuvier’s work on comparative anatomy, and developed rapidly in the 19th century. 

Paleontology lies on the border between biology and geology, but differs from archaeology in that it excludes the study of morphologically modern humans. It now uses techniques drawn from a wide range of sciences, including biochemistrymathematicsand engineering. Use of all these techniques has enabled paleontologists to discover much of the evolutionary history of life, almost all the way back to when Earth became capable of supporting life, about 3,800 million years ago. As knowledge has increased, paleontology has developed specialized sub-divisions, some of which focus on different types of fossil organisms while others studyecology and environmental history, such as ancient climates.

(Source: Wikipedia)

9th June, 2013

DNA Evidence

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DNA can be an effective identifier if used intelligently. What are some potential sources of DNA investigators can use?

  • Blood is an excellent source of human DNA. DNA is present in white blood cells of humans, but not red blood cells which lack nuclei. A dime-sized spot of blood, approximately 50 µl in volume, is enough DNA for a typical VNTR analysis.
  • DNA from sperm heads is usually the most important source of DNA evidence for sexual assault cases. Five µl of semen contains approximately the same amount of DNA as 50 µl of blood. Special extraction methods are required to release DNA from sperm heads. Consequently sexual assault samples can be differentially extracted. The first extraction yields primarily DNA from epithelial cells of the victim, and the second extraction yields primarily semen DNA.
  • Saliva contains cellular material. DNA can be extracted from bite marks, cigarette butts, postage stamps on envelopes, and envelope flaps for DNA analysis. In fact, the “Unabomber” was convicted partially on DNA evidence from a letter-bomb he mailed that did not explode.
  • The hair follicle at the base of human hairs contains cellular material rich in DNA. In order to be used for DNA analysis, the hair must have been pulled from the body — hairs that have been broken off do not contain DNA.
  • Any body tissue that has not been degraded is a potential source of DNA.
  • Bone is one of the best sources of DNA from decomposed human remains. Even after the flesh is decomposed, DNA can often be obtained from demineralized bone. DNA from bone has been used to identify the repatrioted bones from Vietnam era servicemen, and the remains of the White Russian Romanov family who were executed during the Bolsheviek revolution.
  • Like bones, teeth can also be an excellent source of DNA, long after the rest of the body has decomposed.
  • Urine itself does not contain DNA, but it may contain epithelial cells, which do contain DNA. Most healthy individuals, however, do not excrete epithelial cells in their urine.

(Source: biology.arizona.edu)

9th June, 2013

Subdivisions of Forensic Science

There are many fields of science that can be utilized in a criminal investigation, leading to different subdivisions of forensic science. Among them are:

  • Forensic anthropology is the application of physical anthropology in a legal setting, usually for the recovery and identification of skeletonized human remains.
  • Forensic botany is the study of plant life in order to gain information regarding possible crimes.
  • Forensic chemistry is the study of detection and identification of illicit drugs, accelerants used in arson cases, explosive and gunshot residue.
  • Forensic entomology deals with the examination of insects in, on and around human remains to assist in determination of time or location of death. It is also possible to determine if the body was moved after death using entomology.
  • Forensic geology deals with trace evidence in the form of soils, minerals and petroleum.
  • Forensic meteorology is a site-specific analysis of past weather conditions for a point of loss.

Read more here. 

2nd June, 2013

Voting Now Open!

Oh, I suppose I should pop another poll up here… Voting will remain open throughout the week!

Theme for 6/9
  
pollcode.com free polls 

26th May, 2013

This plate, from a later book by Ernst Haeckel, shows a selection of vertebrate embryos from fish to human at three development stages. It was meant to illustrate the similarity between human and animal embryos. Haeckel explained that this is more complete at early stages and retained longer between more closely-related groups.
Haeckel’s scientific opponents accused him of drawing inaccurately to support his theories, and religious enemies taunted him with charges of forgery. His pictures were nevertheless very widely used in textbooks in the 20th century.

This plate, from a later book by Ernst Haeckel, shows a selection of vertebrate embryos from fish to human at three development stages. It was meant to illustrate the similarity between human and animal embryos. Haeckel explained that this is more complete at early stages and retained longer between more closely-related groups.

Haeckel’s scientific opponents accused him of drawing inaccurately to support his theories, and religious enemies taunted him with charges of forgery. His pictures were nevertheless very widely used in textbooks in the 20th century.