202 research outputs found
Figure 1 in Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes
No full textFigure 1. Distribution of species of the speckled rattlesnake (Crotalus mitchellii) species complex in western North America. Symbols represent sampling locations and indicate species and populations recognised in this publication.Published as part of Meik, Jesse M., Schaack, Sarah, Flores-Villela, Oscar & Streicher, Jeffrey W., 2018, Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes, pp. 989-1016 in Journal of Natural History 52 (13-16) on page 990, DOI: 10.1080/00222933.2018.1429689, http://zenodo.org/record/517455
Crotalus thalassoporus Meik & Schaack & Flores-Villela & Streicher 2018, sp. nov.
No full textCrotalus thalassoporus sp. nov. (Figure 5; Table 3) Crotalus mitchelli pyrrhus, Seib 1978, in part. Crotalus mitchellii, Grismer 2002b, Murphy and Aguirre-Léon 2002, Meik et al. 2012a, in part. Crotalus pyrrhus, Meik et al. 2015, in part. Description A diminutive insular species of speckled rattlesnake with overall pale appearance; background colouration tan to pinkish with a series of 27–40 indistinct blotches; blotches usually only slightly darker than ground colour, pinkish to pale brown, often appearing faintly rust-coloured; dark speckling on body is faint. Tail with 3–5 bands, last two or three distinctly black with pale cream interspaces. The head is similar in colouration to the body, but often with few dark specks, more conspicuous than stippling on trunk; grey postocular stripe indistinct. In colour pattern, C. thalassoporus is similar to C. angelensis, and in both species the anterior scales of the dorsal body blotches are tipped posteriorly with dark brown or black. A single row of nasorostral scales precludes contact between rostral and prenasal scales. Variation in standard phenotypic characters is presented in Table 3. Diagnosis The presence of nasorostral scales distinguishes the new species from all congeners except for species of the C. mitchellii complex. From C. mitchellii the new species differs in having typically fewer dorsal scale rows (21.5–22 vs 25), fewer subcaudals (16–22 vs 20–24), fewer temporal scale rows (7 vs 8), fewer supralabials (14 vs 16), fewer interrictals (22–23 vs 28), fewer prefrontals (18–20 vs 30–31), colour pattern (pale tan, pinkish, or beige ground colour with indistinct rust-brown blotches vs variable colour pattern), and smaller adult body size. From mainland populations of C. pyrrhus the new species differs in having typically fewer tail bands (3–4 vs 4–6), fewer dorsal scale rows (21.5–22 vs 25), fewer temporal scale rows (7 vs 8), fewer supralabials (14 vs 16), fewer interrictals (22–23 vs 29), fewer prefrontals (18–20 vs 27–34), colour pattern (pale tan, pinkish, or beige ground colour with indistinct rust-brown blotches vs extremely variable), and smaller adult body size. From C. angelensis, the new species differs in having typically fewer tail bands (3–4 vs 5–8), fewer dorsal body blotches (31–32 vs 40–41), fewer dorsal scale rows (21.5–22 vs 27), fewer subcaudals (16–22 vs 20–25), fewer ventrals (169.5–174 vs 182–188), more supralabials (14 vs 13), fewer interrictals (22–23 vs 29–30), fewer prefrontals (18–20 vs 25–26), and smaller adult body size. From C. polisi, the new species differs in having typically fewer tail bands (3–4 vs 5–6), fewer dorsal body blotches (31– 32 vs 40–42.5), fewer subcaudals in females (16 vs 17), more ventrals in females (174 vs 169), fewer interrictals in males (22 vs 26), fewer prefrontals (18–20 vs 21–27.5), and colour pattern (pale tan, pinkish or beige ground colour with indistinct rust-brown blotches vs slate or charcoal grey ground colour with indistinct blotches). Holotype Subadult male, MZFC-26410, field number JMM-648, collected on 19 March 2010 by Jesse M. Meik, Sarah Schaack and Matthew J. Ingrasci. Rostral plate is as high as broad (2.2 × 2.2 mm), separated from the prenasal scales by 3/2 nasorostral scales; internasal scales 2, with an additional tiny scale interpositioned at the anterior suture and in contact with dorsal edge of rostral. Head scalation highly irregular, making some scale designations ambiguous. Distinct canthal scales absent, but approximately 22 knobby scales of variable size and shape in prefrontal area; interocular scales 7; loreal scales 3/3, irregularly shaped; preocular scales 2/2, prefoveal scales 11/8, irregularly shaped, precluding contact between nasal scales and supraocular scales; subocular scales separated from supralabials by two scales at midpoint of eye; supralabial scales 15/15; infralabial scales 17/16; interrictal scales 24; dorsal scale rows at midbody 23; ventrals 169 (exclusive of three preventrals); subcaudal scales 21, undivided (except distal 3, which are divided); rattle fringe scales 10; rattle segments 3, chain incomplete. Measurements. SVL, 341 mm; tail length, 28 mm; head length (rostral plate to articulation of mandible with quadrate), 18.5 mm; head width (at widest point just anterior to articulation with mandible), 15.7 mm; proximal rattle segment width, 6.7 mm. Colouration and pattern in preservative. Overall ground colouration dirty cream with faint speckling; head with few faint grey specks; lateral surfaces of head with medium grey suffusion, labial scales with cream spots; ventral surface of head cream, immaculate, ventral surface of trunk cream with diffuse black specks; 37 indistinct body blotches only slightly darker than ground colour, some with pale centres, all primary dorsal blotches wider than long with exception of first four, fusing with faint lateral blotch series over posterior third of body to form crossbands; dark maculations on anterior and posterior margins of blotches give the impression of faint transverse bars along the length of the body; five tail bands, distal three black and two scales long. Type locality Piojo Island, Municipality de Ensenada, Baja California, Mexico. Coordinates: N 29.018 W 113.465 (Figure 5). Type deposition Holotype at MZFC-UNAM; paratypes at MZFC-UNAM (MZFC 26411, MZFC 26412) and at UTAARDRC (UTA R-59766, UTA R-59767). Etymology The specific name is derived from the Greek word meaning ‘seafarer’, and is a reference to the apparent historical introgression we note between this taxon and the population of speckled rattlesnakes on Smith Island, most likely resulting from oversea dispersal of propagules from Piojo Island (see Discussion).Published as part of Meik, Jesse M., Schaack, Sarah, Flores-Villela, Oscar & Streicher, Jeffrey W., 2018, Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes, pp. 989-1016 in Journal of Natural History 52 (13 - 16) on pages 1006-1008, DOI: 10.1080/00222933.2018.1429689, http://zenodo.org/record/517455
Interactive Whiteboards in the Secondary Mathematics Classroom
No full textTeaching and Learning Department Capstone ProjectOne issue that today's teachers face is figuring out ways to get students motivated about learning, especially in the area of mathematics. In the past, teachers have utilized computers with projector screens and internet tools, such as Java applets, to demonstrate the dynamic nature of mathematics in an effort to motivate students. More recently, researchers and developers have introduced a new - though pricey - technological tool to the market in order to promote critical thinking and interactive learning in the classroom: the interactive whiteboard. The interactive whiteboard has the ability to run programs and demonstrations much like the computer-projector screen set-up, but with the added interactive capabilities.
The interactive whiteboard is designed to address specific known problems that learners face in terms of motivation, interest, challenge, interaction, and brain-based learning principles. Using the interactive whiteboard, teachers and students can manipulate images directly on the board instead of from behind a computer desk. The boards can also store all notes made on the presentations for future reference, making review of material easier and more accessible. Additionally, authentic and formative assessments are made easier through the use of the interactive whiteboard. Motivation is key to getting students to learn, and the interactive whiteboard is a step in the right direction to getting students motivated to learn mathematics. Challenging students is a way to help motivate them, as long as the task is not overly challenging, and the interactive whiteboard makes it easier for teachers to appropriately challenge their students. Just as motivation is important if learning is to take place, so too are the brain-based education principles - novelty, movement and intensity. The interactive whiteboard is a tool that, if used to its full extent, can increase novelty, movement and intensity in the mathematics classroom. That being said, training is a vital part of implementing the interactive whiteboard in the classroom if it is to be used to its full potential. Teachers must be provided with periodic trainings and continuing support systems for using the technology in order to get the most effective use out of the tool.
Conclusive findings have yet to be established on whether using interactive whiteboards in the mathematics classroom significantly improves student test scores. However, the qualitative data that has been collected has been largely in favor of the use of the boards due to the positive affect they seem to have on students' levels of attentiveness and excitement. Schools and principals should have reason to be excited about this new technology, but must exercise caution before purchasing one or more of the boards: arrangements must be made for sufficient training and ongoing support and all those involved must understand the realistic expectations from using an interactive whiteboard the whiteboard will not single-handedly improve student test scores, but, if used properly, it can help motivate and engage more students, which can lead to better learning and performance.Peabody College of Education and Human DevelopmentDepartment of Teaching and Learnin
Crotalus polisi Meik & Schaack & Flores-Villela & Streicher 2018, sp. nov.
No full textCrotalus polisi sp. nov. (Figure 5; Table 3) Crotalus mitchellii, Grismer 2002a, Murphy and Aguirre-Léon 2002, Meik et al. 2012a, in part. Crotalus pyrrhus, Meik et al. 2015, in part. Description A diminutive insular species of speckled rattlesnake with overall dusky appearance; background colouration is medium grey with a series of 36–48 indistinct and irregularly shaped dorsal body blotches, usually slate to charcoal grey in colour, only slightly darker than background; tail with 5–8 bands, last several are black with cream interspaces. The head is similar in colour to the body, with dark lateral suffusion and often with a faint postocular stripe and parietal blotches. Pattern is heavily punctated with black specks; blotches are usually wider than long, and merge with secondary lateral series to form muted crossbands on the posterior half of the body. A single row of nasorostral scales precludes contact between rostral and prenasal scales. Variation in selected phenotypic characters is presented in Table 3. Diagnosis The presence of nasorostral scales distinguishes the new species from all congeners except for species of the C. mitchellii complex. From C. mitchellii the new species differs in typically having more tail bands (range of mode or median between males and females of each species is presented for all comparisons: 5–6 vs 3–4), more dorsal body blotches (40–42.5 vs 32–34), fewer dorsal scale rows (23 vs 25), shorter ultimate supralabial scale (slightly longer than high vs twice as long as high), fewer supralabials (14 vs 16), fewer ventral scales in females (169 vs 180), fewer temporal scale rows (7 vs 8), colour pattern (mostly uniform colour pattern of slate or charcoal grey with indistinct blotches vs variable colour pattern), and smaller adult body size. From mainland populations of C. pyrrhus the new species differs in having typically more dorsal body blotches (40–42.5 vs 33–34), fewer dorsal scale rows (23 vs 25), fewer ventrals (168–169 vs 176), fewer temporal scale rows (7 vs 8), fewer supralabials (14 vs 16), colour pattern (mostly uniform colour pattern of slate or charcoal grey with indistinct blotches vs extremely variable), and smaller adult body size. From C. angelensis the new species differs in having typically fewer dorsal scale rows (23 vs 27), more supralabials (14 vs 13), fewer ventrals (168–169 vs 182–188), colour pattern (colour pattern of slate or charcoal grey with indistinct blotches vs buff or pink ground colour with grey to russet hexagonal blotches), and smaller adult body size. From C. thalassoporus, the new species differs in having more tail bands (5–6 vs 3–4), more dorsal body blotches (40–42.5 vs 31–32), more interrictals (25–26 vs 22–23), more prefrontals (21–27.5 vs 18–20), and colour pattern (colour pattern of slate or charcoal grey with indistinct blotches vs fawn, pinkish or beige ground colour with indistinct rust-brown blotches). Holotype Adult female, MZFC-26408, field number JMM-642, collected on 18 March 2010 by Jesse M. Meik, Sarah Schaack and Matthew J. Ingrasci. Rostral plate slightly broader than high (2.5 × 2.2 mm). Head scalation highly irregular, making some scale designations ambiguous. Rostral-prenasal contact precluded by 3/3 nasorostral scales; two internasals contact rostral; distinct canthal scales absent, but approximately 29 knobby scales of variable size and shape in prefrontal area; interocular distance spans a minimum of six scales; loreal scales 4/4, irregularly shaped; preocular scales 2/2, upper prefoveal scales irregular, lower prefoveal scales large and broadly contact first three supralabial scales on both sides; subocular scales separated from supralabials by three scales at midpoint of eye; supralabial scales 14/14; infralabial scales 15/15; interrictal scales 25; dorsal scale rows at midbody 23; ventrals 168 (exclusive of one preventral); subcaudal scales 17, undivided; rattle fringe scales 12; rattle segments 6, button present. Measurements. Snout–vent length (SVL), 445 mm; tail length, 23 mm; head length (rostral plate to articulation of mandible with quadrate), 20.7 mm; head width (at widest point just anterior to articulation with mandible), 19.9 mm; proximal rattle segment width, 8.5 mm. Colouration and pattern in preservative. Head with diffuse black speckling; lateral surfaces of head dusky with faint postocular stripe; labial scales with cream blotches (appearing as ‘blotch negatives’ against surrounding ground colour); ventral surface of head cream with faint black specks on periphery, ventral surface of body also cream with diffuse black specks, becoming more prominent on posterior one fourth of body; 38 dusky grey body blotches with narrow (0.5–2 scales long) cream interspaces; blotches indistinct with ill-defined borders, all wider than long, fusing with faint lateral blotch series over posterior third of body to form crossbands; five tail bands, distal four black and only one to two scales long. Type locality Cabeza de Caballo Island, Municipality de Ensenada, Baja California, Mexico. Coordinates: N 28.971 W 113.479 (Figure 5). Type deposition Holotype at MZFC-UNAM; paratypes at MZFC-UNAM (MZFC 26407, MZFC 26409) and at UTAARDRC (UTA R-59763, UTA R-59764, UTA R-59765). Etymology The specific name is a patronym honouring the late Gary A. Polis of the University of California Davis, a renowned arachnologist and desert food-web ecologist, who died at sea on 27 March 2000 when his research vessel capsised in a gale while returning to Bahía de Los Angeles from an expedition to Cabeza de Caballo Island. In addition to Polis, four other researchers, including postdoctoral fellow Michael D. Rose of UC Davis, and Takuya Abe, Masahiko Higashi and Shigero Nakano of Kyoto University, Japan, perished on that day. Four other UC Davis researchers and students survived the tragedy, and by their accounts, the deceased heroically gave their lives to help ensure their survival.Published as part of Meik, Jesse M., Schaack, Sarah, Flores-Villela, Oscar & Streicher, Jeffrey W., 2018, Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes, pp. 989-1016 in Journal of Natural History 52 (13 - 16) on pages 1003-1005, DOI: 10.1080/00222933.2018.1429689, http://zenodo.org/record/517455
Figure 2 in Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes
No full textFigure 2. Maximum likelihood phylogram constructed from three concatenated mitochondrial gene fragments (ATP, cyt-b and 16S). Nodal support values are posterior probabilities from a partitioned Bayesian analysis. Populations or species discussed in the text are indicated with vertical bars.Published as part of Meik, Jesse M., Schaack, Sarah, Flores-Villela, Oscar & Streicher, Jeffrey W., 2018, Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes, pp. 989-1016 in Journal of Natural History 52 (13-16) on page 998, DOI: 10.1080/00222933.2018.1429689, http://zenodo.org/record/517455
Figure 4 in Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes
No full textFigure 4. Scatterplots of first three axes from linear discriminant analyses of phenotypic data (a), principal component axes of microsatellite alleles (b), principal component axes of concatenated mitochondrial sequences (c), and principal component axes of concatenated nSNP data (d). Colour scheme: Crotalus angelensis = pink, C. mitchellii = red, C. polisi = gold, C. pyrrhus mainland = blue, C. pyrrhus El Muerto Island = black, C. pyrrhus Smith Island = brown, C. thalassoporus = purple.Published as part of Meik, Jesse M., Schaack, Sarah, Flores-Villela, Oscar & Streicher, Jeffrey W., 2018, Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes, pp. 989-1016 in Journal of Natural History 52 (13-16) on page 1000, DOI: 10.1080/00222933.2018.1429689, http://zenodo.org/record/517455
It's Not Just The Straws: Investigating the Biology and Genetics of Sea Turtles and the Implications of Climate Change
No full texthttps://rdc.reed.edu/v1/resources/17510c11-1b11-47c8-ab86-9df7072d6c2b/thumb/128.jpgThis undergraduate thesis delves into the evolutionary genetics of green sea turtles, aiming to uncover insights into their population dynamics, implications for conservation efforts; and newer perspectives on the consequences of extinction. Through a combination of literature review, bioinformatics analysis, and integration of historical and environmental data, this thesis addresses critical questions of green sea turtle populations within an evolutionary genetics framework. By examining patterns of genetic diversity and population structure, I intend to shed light on the adaptive potential of green sea turtles and their capacity to cope with environmental challenges, especially in our current climate crisis. Furthermore, this thesis examines the impact of anthropogenic activities - including habitat loss, pollution, and climate change - on the genetic health and resilience of green sea turtle populations. By integrating genetic data with ecological and environmental parameters, this analysis explores the intricate interplay between genetic factors and environmental stressors, offering insights into the driving factors behind population decline. Ultimately, this research presents evidence-based conservation strategies for safeguarding sea turtle’s long-term survival, in the hope of contributing to their preservation and the maintenance of healthy marine ecosystems
Breath of the Wild: Analyzing Intraspecific Variation in Metabolic Rate Using Oxygen Respirometry in Daphnia magna
No full texthttps://rdc.reed.edu/v1/resources/336ba3ce-c861-4e1c-b170-0f24d18d38f5/thumb/128.jpgMetabolism is the biological system of chemical pathways that allow organisms to process nutrients and transform them into energy to sustain the body and build macromolecules. Because there are many working parts involved with metabolism and its chemical pathways, many factors that can influence the rate at which it takes place including the various mechanisms used to maintain homeothermy, variation in body size or activity levels, and abiotic factors like external temperature and stress. Many components of metabolic function have a genetic component and thus can vary among genotypes and evolve over time. Respirometry is a method used to measure oxygen uptake, and the exchange of oxygen and carbon dioxide within an isolated space over a period. In this study, respiration was measured in 105 Daphnia magna individuals across a total of 6 different genotypes of D. magna at two developmental stages. These genotypes originated from Finland, Germany, and Italy with 2 genotypes from each population. By comparing the metabolic rate across different genotypes of D. magna, we can build a stronger understanding of how much genotype variation impacts the metabolic rate and learn more about respirometry as a tool for understanding metabolism
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