The animal weapons arms race Essay Example | Topics and Well Written Essays - 500 words

The animal weapons arms race - Essay Example The show is called science frantic, and the person hosting the show was Jordan Koski. The guest on the show is Douglas Emlen, who is the author of a book named animal weapons – the evolution battle. Douglas is also a professor of biology and lectures at the University of Montenor. I was amazed to realize that it was possible to conduct researches on the extremeness of animal weapons. Douglas claimed that the research leading to writing his book started with watching clips of animal fights. The professor had keen interest in small animals such as dung battles. He claimed that the weapons carried by small animal were very dangerous considering their body sizes (Science-Friday retrieved from http://www.sciencefriday.com/playlist/#play/segment/9594). It was interesting to realize that most fights among small animals were all because they needed access to females. Douglas noted that some animals had deadly weapons since they cannot swim fly or run fast to catch their prey. He gives the example of Smilodon, which has 7 inch canine teeth but cannot run after its prey. I was amazed to realize that some animals had to lose certain minerals in their body in order to make their weapons more deadly. He also noted that some species with fierce weapons had stunted testes and small genital organs. Some animals use their fierce weapons to scare away other animals of the same species. It overwhelmed me know that animals with the most vicious weapons fought less and were rarely involved in battles. He discussed an exceptional case where female animals are fiercer than their male counterparts. He said that Jacana females have bigger weapons that than Jacana males since the males take care of the youngness. The females have to fight for access to males, and hence they develop fierce fighting weapons (Science-Friday retrieved from

Genetic Fingerprinting in Paternal Testing and Forensic Science Research Paper

Genetic Fingerprinting in Paternal Testing and Forensic Science - Research Paper Example Introduction Genetic fingerprinting is a technique that relies on exploiting the differences between human DNA sequences, particularly in variable number tandem repeats (VNTRs), for identification. Predominantly the technique is used in paternity testing and the forensic sciences, and can be used as evidence in a criminal trial (Sheindlin 1996). The use of these VNTRs relies on the fact that these are highly variable between non-related humans and so any matches that are made, either between two individuals or forensic evidence and an accused, is not likely to arise by chance (Toth 1997). The purpose of this essay is to explore the applications of genetic fingerprinting technology in paternal testing and forensic science, as well as highlighting some of the pitfalls of using such technology, particularly in a legal setting. Genetic Fingerprinting The principles of genetic fingerprinting rely on the differences between human genomic sequences. Although 99% of the human genome is the s ame in structure, there are certain differences (known as polymorphisms) that are distinctly different in individuals that are not related. For example, VNTRs, particularly short tandem repeats (STRs or microsatellites) are molecular markers that are extremely prone to mutation (Gill et al 1987). All human genomes contain STRs, but these vary hugely between populations and within them, to the extent that 1 in 5 million people will have the same sequence by chance (Jeffreys, Wilson & Stein 1985). Any technique that can ascertain whether two DNA samples match will, therefore, reduce the possible number of perpetrators hugely, making genetic fingerprinting immensely useful to the law. Related individuals also have similarity due to the STRs being co-dominant; each offspring will have one allele from each parent. It is this fact that makes genetic fingerprinting useful in paternity testing (Jeffreys et al 1985). Genetic profiling can occur in a number of ways. One of the most common is polymerase chain reaction (PCR) which amplifies the amounts of a specific DNA sequence, which is evidently useful when working with known STRs. This is achieved using oglionucleotide primers as well as a DNA polymerase, with the primers targeting a specific STR and the DNA polymerase amplifying them for analysis (Welsh & McClelland 1990). It is important that multiple STRs are analysed using PCR, because each individual one can be shared by around 5-20% of the population (Sheindlin 1996). Using multiple STRs for analysis greatly increases the probability that an exact match will be made for whatever reason the analysis is occurring. This method relies on the principle of independent assortment, and the product rule for probabilities means that the chance of someone having the same alleles at multiple STR loci decreases with the number of loci analysed. Genetic Fingerprinting in Paternal Testing It is because of the nature of VNTRs that makes them useful for paternal testing; because they are co-dominantly inherited, each individual will inherit one copy from each parent. This means that when trying to ascertain paternity, an individual will have the same sequence at each VNTR locus as the father (as well as one from the mother at the corresponding locus). If the mothers VNTR genotype is known, then these