Species-area Relationship of Herpetofaunas in West Indies

Species-area Relationship of Herpetofaunas in West Indies De Gao 1. Introduction 1.1. Biodiversity and crisis on West Indies Oceanic islands, due to their discrete geographic isolation, differ distinctly from terrestrial  ecosystem, offer great opportunities for species conservation, and are regarded as the natural  laboratory for the study of biogeography and evolutionary ecology (Adsersen, 1995; Crawford  and Stuessy, 1997; Ricklefs and Bermingham, 2008). Island habitat heterogeneity and the gene  flow barrier between the island and its neighboring islands or land are the most important driving  forces leading to new species differentiation and formation (Cherry et al. 2002). The colonized  species from continents or nearby islands are then subjected to unique evolutionary processes,  for example, geographic isolation, character displacement, and adaptive radiation. The  accumulated mutations gradually and ultimately make colonized species into new indigenous  species that are genetically different from the original one. One of the most distinctive features of  the biota on oceanic is lands is the large number of endemics occurring in small areas (Francisco-Ortega et al. 2000). West Indies was identified as a biodiversity hotspot by Myers et al. (2000). A significant  percentage of the Earth’s known terrestrial biota is distributed on islands of the West Indies,  many of these species are endemic to the region, to individual islands, and even to isolated areas  within some islands (Hedges, 2001). But a large majority of the vast complex of islands in West  Indies is changing rapidly, resulting in dramatic alterations of habitats, and nearly all of them are  mediated by human activities (Powell and Henderson, 2012). Small population size, gene drift,  isolated gene flow, and the complexity of island environment have already made the endemic  herpetofaunal species easy to be endangered or extinct, human disturbances undoubtedly worsen  the situation. Therefore, critical conservation concerns in West Indian region are increasingly  important and required. 1.2. Species-area relationship (SAR) The species-area relationship is one of the most fundamental patterns in macroecology and an  important tool in assessing species diversity, extinction rates and species hotspots (Tjà ¸rve, 2009). According to the equilibrium theory (MacArthur and Wilson, 1967), the relationship between  immigration and the extinction of species to island depends on the island size and its distance to  mainland. MacArthur-Wilson’s theory provided impetus for numerous studies on species-area  relationships (SARs) that have provided biological interpretations for several taxa and have  suggested factors and mechanisms that can determine species richness (Simaiakis et al. 2012). And the theory has an enormous influence on perspectives of species conservation and nature  reserves design. The main objective of this chapter is to discuss SARs for herpetofaunas in West Indies regions,  with the aim of discover which factors may determine their distribution over the whole range of  island sizes. We choose to fit some candidate models including the power model and some  sigmoid models to see whether a J-shaped part exists at the lower end of the curve. Small-island  effect (SIE) holds that, on islands smaller than a certain critical minimum area, one cannot  observe an increase in species number with increasing area (Simaiakis et al. 2012). We choose to  fit candidate models including the power model and some sigmoid models to see whether a J-shaped part exists at the lower end of the curve. If the best fitted model has a sigmoid shape, a J-shaped part will exist at the lower end, and then we accept SIE. If the best fitted model has a  convex shape, a J-shaped part will not exist at the lower end, and then we deny SIE. There are  also other reasons why it is so important to know the shape of species-area curve. Based on the  curve shape, we could estimate total species diversity from limited numbers of samples, or  estimate species extinction as a result of habitat loss and fragmentation (Tjà ¸rve, 2003). Candidate species-area models are proposed from two sources. The first source is species-area  literature which has traditionally fit data with power or exponential models, the second source  involves a broader search of the literature for models that increased monotonically to an  asymptote (Flather, 1996). Although the shape of the curve has been extensively debated over the years, power and  exponential curves are the most commonly applied and best known ones, lately, an increasing  number of authors have argued some SARs are perhaps best represented by functions that are  sigmoid in arithmetic space and there are also a number of recent studies where sigmoid models  have been fitted to empirical data (Tjà ¸rve, 2003). Some sigmoid models behave similar with  others, for instance, the Extreme value function behaves quite similar to the Logistic and  Gompertz models; The Cumulative beta-P distribution behaves similarly to the Weibull  distribution (Tjà ¸rve, 2003). 2. Aims In this study, we are trying to solve 3 questions: Question 1: What is the species-area relationship (SAR) for herpetofaunas in West Indies? Is the  SAR same for native and invasive species? And is it the same among each animal group  classification under amphibian and reptile? Question 2: Due to human’s help, invasive species are supposed to have a higher dispersal  ability as compared to the native. So, in the linear form of the power model (LogS/LogA) is there  a higher z-value for the invasive species than the native species? Question 3: What geographic factors may determine species richness over the whole range of  island sizes? Are these factors also applicable to other group of islands that located in similar  latitude areas to determine their species richness? 3. Material and Methods Data on species occurrences originate from Powell and Henderson (2012). Multiple basemaps in  ArcMap 10 and ArcGlobe 10 will be used to digitize islands map. We use different scales to  digitize islands with various areas. Fractal Analysis will be used to estimate the perimeters at a  uniform scale (Farina, 2007). For comparisons of the fit of different models, the Akaike’s  information criterion (AIC) was applied (Burnham and Anderson, 2002). Model selection  analyses will run using â€Å"mmSAR† package (Guilhaumon et al. 2010) for the R statistical and  programming environment (R Development Core Team, 2011). Aim 1: Model selection we use the 8 most general models composed in â€Å"mmSAR† package (Guilhaumon et al. 2010) to  fit the data, which include 5 convex models (Power, Exponential, Negative exponential, Monod,  Rational function) and 3 sigmoid models (Logistic, Lomolino, Cumulative Weibull). Aim 2: LogS/LogA linear regression We analyze the linear function of the LogS/LogA and compare parameter values with vertebrates  from global oceanic islands (Triantis et al. 2012). Aim 3: Find out the geographic factors affect species richness/Steps Initially selected variables are X1 Distance to mainland X2 Latitude of island centroid X3 Longitude of island centroid X4 Island No. within 0.1km X5 Island No. within 0.1-1km X6 Island No. within 1-5km X7 Island No. within 5-10km X8 Islands Area within 0.1km X9 Islands Area within 0.1-1km X10 Islands Area within 1-5km X11 Islands Area within 5-10km X12 Area of the island X13 Perimeter of the island X14 Perimeter/Area X15 Percentage of vegetation X16 Percentage of human area X17 Rivers within the island X18 Invasive spp. within the island X19 Percentage of invasive spp. X1 and X3 are used to examine species dispersal from mainland; X2 is used to examine the  nearness to equator; X4, X5, X6, X7 are used to examine stepping stones in each loop circle; X8,  X9, X10, X11 are used to examine total area of stepping stones in each loop circle; X12 is used to examine area effect; X13 and X14 are used to examine shape (irregularity) of island; X15,  X17 are used to examine habitat quality; X16, X18, X19 are used to examine human disturbance  and invasive species. Principal Component Analysis and Hierarchical Partitioning Analysis will be made based on the  residuals distribution of LogS/LogA linear regression to examine which geographic factors are  the significant contributions of species richness in West Indies.

The Advancement of Technology Essay -- Military Technology

War has been a reoccurring part of America’s history for the past 230 years. From the 1700s to the present, America has gotten into many different situations and turmoil, which eventually lead to the wars we currently study and know about today. Technological advancements in warfare were necessary and a great obligation during times of war. This was pursued with drastic improvement. From the transformation of the use of smoothbore muskets during the Civil War to the industrial revolution leading to weaponry innovations post civil war, the nature of warfare dramatically changed. These developments proved to be proficient in battle. In the midst of these hundreds of years, while many technological advances demonstrated to be efficient in battle, the machine gun was one of the most significant advancements in technology that changed the face of warfare through its transformation of operations and strategy. During the civil war before the introduction of the machine guns, union soldiers primarily used smoothbore muskets. â€Å"The rifle’s low muzzle velocity and consequent high parabolic trajectory made for difficult long-range shooting, especially since soldiers engaged in little target practice and received virtually no training in estimating distances or in using the adjustable sights to compensate for the bullet’s curved flight. The tangled terrain of most battlefields—and the black powder smoke that engulfed every battle—often rendered enemy soldiers invisible until they were within smoothbore range† (Hess 288). This was assumed to be the reason of why the war was prolonged, and the combat losses were higher during the smoothbore era. Also with an ability of only firing a â€Å"maximum of three rounds per minute† (Howey), this rat... ...Goldsmith, Dolf L., and R. Blake. Stevens. The Devil's Paintbrush: Sir Hiram Maxim’s Gun. Toronto: Collector Grade Publications, 1989. Print. 2. Hess, Earl J. The Rifle Musket in Civil War Combat: Reality and Myth. Lawrence, Kan: University Press of Kansas, 2008. Print. 3. Howey, Allan W. "Weaponry: The Rifle-Musket and the Minià © Ball  » History Net." History Net. Weider History Group, Oct. 1999. Web. 12 May 2012. . 4. Lee, Loyd E. World War II. Westport, CT: Greenwood, 1999. Print. 5. Popenker, Max R. "Modern Firearms - MachineGuns." Max R. Popenker, 1999-2010. Web. 10 May 2012. . 6. Simkin, John. "Machine-Gun." Spartacus Educational - Home Page. John Simkin. Web. 10 May 2012. .

Benefits of Low Student Teacher Ratio

The Benefits Derived From a Low Student –Teacher Ratio Albert Fuller American Intercontinental University English Composition II What are the possibilities and impacts of a low student-teacher ratio and how can it be beneficial to both students and teachers alike. Imagine yourself in a class of 30 or more students, you are eager to learn but find it hard to grab the attention of the teacher.You feel lost in a class of pupils and you don’t know if you are going to absorb the lesson of the day. Sitting at your desk wishing that your instructor focused more time on the subjects that you didn’t understand; you find yourself looking for opportunities to refocus attention on you. Hoping to gain the knowledge and intellect that will help prepare you for college, you soon realize that your teacher being overworked often times overlooks your progress.Many students in the world today face these problems. There are multiple signs that point to how reducing class sizes will show an improvement in several areas that are affecting educators and students and once these areas are controlled benefits will be shared by both groups. Students benefiting from the personalized learning experience of smaller classes have a higher probability of entering institutions of a higher level of education.A published journal by Finn & Gerber (2005) estimate that the large studies performed by three states comparing smaller to larger class sizes arrived at the same conclusion, â€Å"that smaller class sizes result in substantial gains in student achievement which sustain to graduation and beyond†. These were the STAR study in Tennessee, the SAGE studies in Wisconsin and the CSR studies in California. These combined studies measured how mixed variations of the learning environment have an impact on percentages relating to educational progress.Konstantopoulos (2008) has pointed to a fact that shows that the smaller learning environment in inner city schools has been s hown to provide students more time to learn details of lessons that would otherwise be cut short in larger classes. Teachers from inner city schools have reported that their students, when placed in a smaller class size are retaining information being delivered simply because they are more abled to review the lesson immediately with students that haven’t gasped the delivered concepts Konstantopoulos (2008).The students feel the benefit of education retention from the smaller classes and more prepared when entering college because of the detail in learning that was available to them during secondary education. A direct consequence of the failure to adequately fund public schools is budget restraints and students in low funded states have had to suffer from some of the largest class sizes in America due to this. State level government has been forced to choose between funding school programs and providing competitive pay to teachers.As a consequence of low school funding, many 9th Graders across the U. S. have the lowest percent of college completion. Burtless (1996) Causing educators to lose focus on the quality of education a student receives, many teachers believe that one of many drawbacks to House Bill 2261 is how it eliminated even the inadequate floor for school funding of the Basic Education Act and replaced it with class size funding at whatever level the State legislature wanted to fund schools during a particular year, this was a major one of many drawbacks to Bill 2261.Konstantopoulos and Chung (2009) Many scholars have cited that the percentage based funding the states have devised now leaves low-income areas of a state forced to have higher student-teacher ratios than other areas of the state; this has cause teachers to lose focus on educating students and be more so spending their days completing various paperwork. These teachers enjoy their profession less than teachers in low student-teacher ratio schools. Burtless (1996) Smaller classes would benefit teachers as well.They will have a smaller group of students to manage which with provide less chance of class disruptions and they will be able to progress through planned lessons in a smoother pace. Due to the low funding of some states, teachers with larger classes are focused on following lesson plans and paperwork with no time to use forms of creative instruction Burtless (1996). Without the individuals creative instruction students surveyed have reported that the information being delivered appears repetitive and less interesting causing them to lose focus and not retain the information being delivered.The focused learning experience that the smaller environment provides will boost class participation and will encourage students to have higher educational goals and will benefit these students in future endeavors. Fewer students will feel a lack of learning in a smaller learning environment. The smaller classes have shown improved statistics in academic behavior an d from this change we are able to see the need for structure in the class along with quality one-on-one time with teachers.Konstantopoulos (2008) Students in smaller class settings are able to retain focus and teachers are able to maintain direction. Fewer students in a class would allow teachers to monitor how well students are retaining information, reduce behavior issues and would prevent students from going off task. Parker (2008) With larger classes, teachers spend more time reviewing course material for those that are behind rather than moving on in subject matter.With the smaller class sizes, educators will be able to cover more subject matter and, in turn, students are shown to learn more than has been expected for that grade level. In conclusion, smaller classes are shown to improve the quality of learning that is currently being provided in larger classes. Students across America have taken part in studies discussed in this essay and experts agree that the benefits of a sm aller class have long lasting impacts on student relations with teachers and nourish the mind to achieve higher educational goals.Although funding in some states do not support smaller sized classrooms, reducing the class size has shown to have a significant impact on the effort a teacher uses in education, the participation of students in smaller classes when faced with more one-to-one instruction, behavior changes in smaller classes, and the increase in the level of education smaller students receives. References: Burtless, G. (1996) Does Money Matter? : The Effect of School Resources on Student Achievement and Adult Success ISBN 0-8157-1275-8 Konstantopoulos, Spyros; Chung, Vicki (2009). â€Å"What Are the Long-Term Effects of Small Classes on the Achievement Gap?Evidence from the Lasting Bene? ts Study†. American Journal of Education 116 (1): 125–54. Konstantopoulos, Spyros. (2008). â€Å"Do Small Classes Reduce the Achievement Gap between Low and High Achievers? Evidence from Project STAR. † Elementary School Journal 108 (4): 275–91. Parker, L. (2008). Little Wonders http://www. aeufederal. org. au/Publications/AE/Spr08pp18-20. pdf Finn, J. D. , & Gerber, S. B. (2005) Small Class Sizes in Early Grades, Academic Achievement, and Graduating From High School, Journal of Educational Psychology, (97) (2) 214-223 http://www. apa. org/pubs/journals/releases/edu-972214. pdf

Using PHP and HTML on the Same Page

Using PHP and HTML on the Same Page Want to add HTML to a PHP file? While HTML and PHP are two separate programming languages, you might want to use both of them on the same page to take advantage of what they both offer. With one or both of these methods, you can easily embed HTML code in your PHP pages to format them better and make them more user-friendly. The method you choose depends on your specific situation. HTML in PHP Your first option is to build the page like a normal HTML web page with HTML tags, but instead of stopping there, use separate PHP tags to wrap up the PHP code. You can even put the PHP code in the middle if you close and reopen the ?php  and ? tags. This method is especially useful if you have a lot of HTML code but want to also include PHP. Heres an example of putting the HTML outside of the tags (PHP is bold here for emphasis): html titleHTML with PHP/title body h1My Example/h1 ?php//your PHP code goes here? bHere is some more HTML/b ?php //more PHP code ? /body /html As you can see, you can use any HTML you want without doing anything special or extra in your PHP file, as long as its outside and separate from the PHP tags. In other words, if you want to insert PHP code into an HTML file, just write the PHP anywhere you want (so long as theyre inside the PHP tags). Open a PHP tag with  ?php  and then close it with  ?  like you see above. Use PRINT or ECHO This other way is basically the opposite; its how youd add HTML to a PHP file with PRINT or ECHO, where either command is used to simply print HTML on the page. With this method, you can include the HTML inside of the PHP tags. This is a good method to use for adding HTML to PHP if you only have a line or so to do. In this example,  the HTML areas are bold: ?php Echo html;EchotitleHTML With PHP/title;EchobMy Example/b;//your php code herePrintiPrint works too!/i; ? Much like the first example, PHP still works here regardless of using PRINT or ECHO to write HTML because the PHP code is still contained inside the proper PHP tags.

3 Examples of Confusion Caused by Missing Words

3 Examples of Confusion Caused by Missing Words 3 Examples of Confusion Caused by Missing Words 3 Examples of Confusion Caused by Missing Words By Mark Nichol In each of the sentences below, omission of a small but key word muddles the statement’s meaning. Discussion after each example explains the problem, and a revision to each sentence provides a clarifying solution. 1. Some organizations still look at privacy and security as a cost/benefit equation, rather than an issue that could create long-term damage. This sentence requires corresponding prepositions preceding the phrases that express conflicting possibilities; otherwise, readers may be unclear as to whether â€Å"an issue that could create long-term damage† is complementary to â€Å"a cost/benefit equation† or whether the former phrase describes something organizations still look at instead of privacy and security: â€Å"Some organizations still look at privacy and security as a cost/benefit equation, rather than as an issue that could create long-term damage.† 2. The agency particularly calls out the need for firms to ensure systems and technologies are resilient to cyberattack and that firms are not exposed to attack during periods of change. The conjunction that is often optional, but it is recommended after ensure so that the reader is not temporarily misled into misunderstanding, for example, that the phrase â€Å"ensure systems and technologies† does not refer to ensuring those things themselves as opposed to ensuring that something about them occurs or is true: â€Å"The agency particularly calls out the need for firms to ensure that systems and technologies are resilient to cyberattack and that firms are not exposed to attack during periods of change.† 3. Respondents from the region are also significantly less likely to believe that the direction of regulatory scrutiny is increasing than other regions. Here, the notion of other regions, rather than a situation occurring in other regions, is compared to the original situation. To clarify the relationship of the key phrases, a preposition should precede â€Å"other regions†: â€Å"Respondents from the region are also significantly less likely to believe that the direction of regulatory scrutiny is increasing than those in other regions.† Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Grammar category, check our popular posts, or choose a related post below:Avoid Beginning a Sentence with â€Å"With†List of Greek Words in the English LanguageAffect vs. Effect

Overview of Spanish Verb Tenses

Overview of Spanish Verb Tenses It almost goes without saying that the tense of a verb depends upon when the verbs action takes place. So it shouldnt be surprising that the Spanish word for tense in the grammatical sense is tiempo, the same as the word for time. In the simplest sense, there are three tenses: the past, present, and future. Unfortunately for anyone learning most languages, including English and Spanish, it is seldom that simple. Spanish also has a tense not connected to time, as well as two types of simple past tenses. Overview of Spanish Tenses Although both Spanish and English have complex tenses that use auxiliary verbs, students often begin by learning four types of simple tenses: The present tense is the most common tense and the one invariably learned first in Spanish classes.The future tense is most often used to refer to events that havent happened yet, but it can also be used for emphatic commands and, in Spanish, to indicate uncertainty about current happenings.The past tenses of Spanish are known as the preterite and the imperfect. To simplify, the first is usually used to refer to something that happened at a specific point in time, while the latter is used to describe events where the time period isnt specific.The conditional tense, also known in Spanish as el futuro hipotà ©tico, the future hypothetical, is different than the others in that it isnt clearly connected with a particular time period. As the name implies, this tense is used to refer to events that are conditional or hypothetical in nature. This tense should not be confused with the subjunctive mood, a verb form that also can refer to actions that arent necessarily real. Verb Conjugation In Spanish, verb tenses are formed by changing the endings of verbs, a process known as conjugation. We sometimes  conjugate verbs  in English, for example adding -ed to indicate the past tense. In Spanish, the process is much more extensive. For example, the future tense is expressed using conjugation rather than by using an additional word such as will or shall in English. There are five types of conjugation for simple tenses: Present tenseImperfectPreteriteFutureConditional In addition to the simple tenses already listed, it is possible in both Spanish and English to form what is known as the perfect tense by using a form of the verb haber in Spanish, to have in English, with the past participle. These compound tenses are known as present perfect, the pluperfect or past perfect, the preterite perfect (limited mostly to literary use), the future perfect and the conditional perfect. A Closer Look at Spanish Tenses Although the tenses of Spanish and English are very much alike- after all, the two languages share a common ancestor, Indo-European, with origins dating to prehistoric times- Spanish has some peculiarities in its tense usage: The differences in the past tenses of ser and estar can be especially subtle.Sometimes, the word used to translate a Spanish verb can vary depending on the tense used.It is possible to describe events that will happen in the future without using the future tense.While the English auxiliary verb would is often an indication that the conditional tense is being used, such isnt always the case.Although the conditional tense is a common one, there are also  conditional sentences that use other forms of verbs.By using estar as an auxiliary verb in the various tenses, it is possible to form progressive verbs that can be used in various tenses.

How did race influence the positions of first-wave feminists Essay - 1

How did race influence the positions of first-wave feminists - Essay Example The agenda of feminist activists included such aspirations as equality with men in the fields of â€Å"education, professional careers, and culture; married women’s economic and legal dependence; sexual and moral double standards; women’s lack of control over their bodies; the drudgery of housework; low wages; and not least, women’s exclusion from politics† (LeGates, p.203). It is quite obvious that disparities between racial and ethnic communities do not feature in this list. This suggests that while racial minorities continuously strived for emancipation during this period, their struggles were recorded independent of the women’s movement. This apparent inconsistency is reflected in the fact that the leading activists of the first-wave feminist movement were largely white women of middle-class socio-economic background. A closer scrutiny of the movement betrays a double standard on part of the reformers, who, it seemed, â€Å"were content to accept the restraints of race and class as natural and inevitable†.(LeGates, p.197) The issue of race was more pronounced in North America compared to Europe. At the time of first-wave feminism, North America was largely inhabited by Caucasians who emigrated from Western European nations in the preceding two centuries. The leaders of feminist movement saw new immigrants from diverse ethnic and racial backgrounds as a threat to their own position of relative privilege. They were only too willing to perpetrate the racial prejudices and discriminatory practices of their male compatriots. As LeGates points out, â€Å"They used statistics to prove the numerical superiority of n ative-born Anglo-European women in the population, contending that the enfranchisement of all women would offset the foreign vote†. (LeGates, 257) The epitome of such attitudes is captured in the following sentiment expressed by Canadian feminist Margaret McAlpine, who advised the prime minister in 1911 that â€Å"Canadian