The Science of Christmas

Total Page:16

File Type:pdf, Size:1020Kb

The Science of Christmas THE SCIENCE OF CHRISTMAS by Tangstar Science T’was the day before Christmas break and all through the school, No one was very attentive, especially the pupils. creatures,(meaning xbyevena xxxxbyplants anda xxxfungi, can glow! The secret behind their glow is called bioluminescence. The The books were already packed away, word bios- comes from the Greek word for “living” and -luminescence comes from the Latin word lumen with 10 minutes to spare, meaning “light”. Organisms create living light in In the hopes that the teacher several ways, but the main way is through producing a light-emitting pigment called luciferin. When this would let them out early, pigment is oxidized (meaning it has some electrons but they all knew t’was rare. removed from it) by an enzyme called luciferase, luciferin will release light. The most familiar The children were day-dreaming of bioluminescent organism is probably the firefly. This creature has a light organ in its abdomen where the toboggan rides on top of a sled. bioluminescence occurs. Some species glow both in While visions of presents and hot the larval stage as well as in the adult stage. There are several reasons why this is useful. Fireflies contain chocolate danced in their heads. a distasteful chemical that turns predators away. The glow signals to predators that they should avoid But before the bell rang, eating the fireflies. As well, the speed and pattern of the flashing male firefly’s abdomen attracts females. the teacher had one final thing to say. It’s been shown that many females prefer males that “Don’t forget to read your can flash faster. Before modern Science of Christmas Article lighting was available, coal miners used to capture fireflies in glass before you go out and play”. jars and use them as a lighting sources in the dark conditions of the coal mine. (1) You might have once heard a teacher say that (3) How could Rudolf have developed his own “science is everywhere!” It’s true. Even Christmas bioluminescence? We know that reindeer (also called time is full of fascinating science. We’ll look into some caribou) live in the Arctic tundra. They like to eat of the most interesting Christmas science in this mainly a type of lichen called reindeer moss. A lichen article. What is the science behind Rudolf’s glowing is a curious two-part creature. It is composed of red nose? Could Rudolf be a girl? Why are Santa’s photosynthetic bacteria that live within the filaments elves so short? Why is Santa’s hair so white? How of fungi. Though we don’t does Santa stay undetected as he delivers his know of any bioluminescent presents? As, well, what you will discover about the lichen, there are over 70 humble turkey will be sure to surprise you. These species of bioluminescent topics will all be explored in this article. Hopefully you fungi, some of which are found are curled up someplace warm with a cup of hot in North America. It is possible cocoa. Sit a spell and read on to learn more. that Rudolf is the only reindeer to have found his own secret (2) See that Nose Glow! Rudolf is Santa’s main patch of lichen that contains bio- reindeer and he’s famous for his glowing red nose. Of luminescent fungi. The glow created course this makes Rudolf special but he is not the only by this type of fungi is called “foxfire”. glowing creature in the world. In fact, many Rudolf has potentially eaten enough ssdfsddfasdf © Tangstar Science of this type of lichen to make his nose glow. But why (7) Do such small people naturally exist among us? A does his nose glow red instead of green (which is the condition called dwarfism leaves people with short color of many lichen)? It’s the blood vessels in his stature. People who are under 4 feet 10 inches tall nose. If you put a flashlight up to your fingers in a are considered dwarves. Dwarfism can be caused by dark room you will see that the light moving through factors which prevent bones from growing to their your flesh glows red as it goes through your blood common length. vessels. Now you know how his nose could glow! (8) Dwarfism is a condition caused by abnormal (4) The Real Story of Rudolfina Besides the mystery genetics or other medical conditions that stunt behind Rudolf’s nose, there’s also some question growth. However, can there be people who are about Rudolf’s biological sex. We have always actually just normally small in size? In 2003, scientists assumed that Rudolf was a boy, but what if Rudolf is discovered the skeleton of a small human that they actually Rudolfina! Most people point to Rudolf’s nicknamed “the Hobbit” in a cave on a small island antlers as proof that he’s a boy, however, reindeer are called Flores, in Indonesia. Later, testing and analysis the only species where the females also grow antlers. would reveal that this small skeleton belonged to an Unlike horns, which are body parts that grow through extinct type of human called Homo floresienis. The an entire lifetime, antlers are structures that are remains were of a 30 year old female who was 3.5 seasonal and fall off and regrow every year. Both feet tall (1m) and roughly weighing 55lb (25kg) when males and females shed and regrow new antlers alive. The scientists named her LB1 and called her Flo. annually. Males grow their antlers to fight each other Further studies revealed that she did not suffer from for mating territory and access to females. Once the any diseases that would have stunted her growth. In mating season is finished in early December, males fact, Flo was not strange for her species at all. On have no more use for their antlers and they get shed average, Homo floresienis adults were under 4 feet at that time because antlers take a lot of energy for tall. The fossil records show that Homo floresienis their bodies to maintain. The females, however, keep probably evolved from Homo erectus that came to the their antlers all through the winter and early spring to island over a million years ago. Homo erectus is an fight each other for food so that they can ensure ancestor of Homo sapiens and was roughly around the adequate nutrition for their growing babies. It’s not same size as modern humans. One hypothesis as to until spring time, when food becomes more plentiful, why Homo floresienis is so small is that after arriving that the females shed their antlers. Due to the timing to Flores, Homo erectus began to rapidly evolve into a of when antlers are shed, there is no way that any smaller form due to a process called insular dwarfism. reindeer with antlers during Christmas could be a boy. (9) Insular dwarfism is seen in situations where large (5) So there you have it! Rudolf is a female reindeer animals become smaller over generations if they are that has found a delicious secret patch of isolated to areas that have limited food resources. bioluminescent lichen. Of course, she’ll keep this to Islands, like Flores, which are food resource poor, are herself so that she’ll be the only one with a “foxfire” prime examples of this. When food is scarce, this is a nose. disadvantage to larger members of a population because there isn’t enough food to maintain the (6) Size Does Matter Besides his reindeer, Santa also optimum health of a large-sized body. Smaller surrounds himself with elves. Technically, elves are individuals in the population will find it easier to small supernatural human-like creatures that maintain better health because they don’t need to originate from Germanic mythology and folklore. find as much food. They will be the ones to survive and pass on their genes for small stature to the next generation. Over time, these conditions favor the evolution of smaller and smaller body sizes. (10) There are plenty of modern day examples. One example is the island fox found on the Channel Islands of California. Island foxes weigh between 2 to 6 lbs while their mainland relatives, the grey foxes, weigh between 8 to 15 lbs. © Tangstar Science Dwarf elephants, antelopes, snakes, tigers, lemurs and many other animals have transformed from bigger to smaller versions due to insular dwarfism. (11) Could Santa have become the beneficiary of insular dwarfism? Perhaps many years ago, Santa invited people to work for him making toys. Due to the limited resources in the North Pole, the people got smaller and smaller throughout the generations until they became so small we began to call them elves. (12) What Nice Hair You Have Santa Santa is easily recognizable because of his red suit, big belly and flowing white hair and beard. Have you ever wondered why Santa’s hair (or anybody’s hair for that matter) is white? (13) Hair color is produced by cells found in the with an increased application of bleach does the follicles of the hair shaft. These cells are called pheomelanin break down leaving the hair without any melanocytes which produce a pigment called melanin pigment. Now that the hair is colorless, it can be which gives hair its color. Melanocytes inject the treated with whatever color the client wants. melanin into the hair shaft as the hair is being created to give hair color. Melanin also happens to be the (16) So what has happened to Santa’s hair? Well, pigment that produces the diversity of skin colors of Santa is old, and as you get older, your melanocytes the different racial and ethnic groups around the stop producing as much melanin.
Recommended publications
  • The Island Rule Explains Consistent Patterns of Body Size 2 Evolution Across Terrestrial Vertebrates 3
    bioRxiv preprint doi: https://doi.org/10.1101/2020.05.25.114835; this version posted September 17, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 1 The island rule explains consistent patterns of body size 2 evolution across terrestrial vertebrates 3 4 Ana Benítez-López1,2*, Luca Santini1,3, Juan Gallego-Zamorano1, Borja Milá4, Patrick 5 Walkden5, Mark A.J. Huijbregts1,†, Joseph A. Tobias5,† 6 7 1Department of Environmental Science, Institute for Wetland and Water Research, Radboud 8 University, P.O. Box 9010, NL-6500 GL, Nijmegen, the Netherlands. 9 2Integrative Ecology Group, Estación Biológica de Doñana, CSIC, 41092, Sevilla, Spain 10 3National Research Council, Institute of Research on Terrestrial Ecosystems (CNR-IRET), Via 11 Salaria km 29.300, 00015, Monterotondo (Rome), Italy 12 4Museo Nacional de Ciencias Naturales, Consejo Superior de Investigaciones Científicas (CSIC), 13 Madrid 28006, Spain 14 5Department of Life Sciences, Imperial College London, Silwood Park, Buckhurst Road, Ascot, 15 Berkshire SL5 7PY, United Kingdom 16 *Correspondence to: [email protected]; [email protected] 17 †These two authors contributed equally 18 19 20 1 bioRxiv preprint doi: https://doi.org/10.1101/2020.05.25.114835; this version posted September 17, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.
    [Show full text]
  • Dome-Headed, Small-Brained Island Mammal from the Late Cretaceous of Romania
    Dome-headed, small-brained island mammal from the Late Cretaceous of Romania Zoltán Csiki-Savaa,1, Mátyás Vremirb, Jin Mengc, Stephen L. Brusatted, and Mark A. Norellc aLaboratory of Paleontology, Faculty of Geology and Geophysics, University of Bucharest, 010041 Bucharest, Romania; bDepartment of Natural Sciences, Transylvanian Museum Society, 400009 Cluj-Napoca, Romania; cDivision of Paleontology, American Museum of Natural History, New York, NY 10024; and dSchool of GeoSciences, Grant Institute, University of Edinburgh, EH9 3FE Edinburgh, United Kingdom Edited by Neil H. Shubin, The University of Chicago, Chicago, IL, and approved March 26, 2018 (received for review January 20, 2018) The island effect is a well-known evolutionary phenomenon, in describe the anatomy of kogaionids in detail, include them in a which island-dwelling species isolated in a resource-limited envi- comprehensive phylogenetic analysis, estimate their body sizes, ronment often modify their size, anatomy, and behaviors compared and present a reconstruction of their brain and sense organs. with mainland relatives. This has been well documented in modern This species exhibits several features that we interpret as re- and Cenozoic mammals, but it remains unclear whether older, more lated to its insular habitat, most notably a brain that is sub- primitive Mesozoic mammals responded in similar ways to island stantially reduced in size compared with close relatives and habitats. We describe a reasonably complete and well-preserved skeleton of a kogaionid, an enigmatic radiation of Cretaceous island- mainland contemporaries, demonstrating that some Mesozoic dwelling multituberculate mammals previously represented by frag- mammals were susceptible to the island effect like in more mentary fossils.
    [Show full text]
  • Reconstructing the Late Cretaceous Haţeg Palaeoecosystem
    Palaeogeography, Palaeoclimatology, Palaeoecology 293 (2010) 265–270 Contents lists available at ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo Preface An island of dwarfs — Reconstructing the Late Cretaceous Haţeg palaeoecosystem Zoltan Csiki a,⁎, Michael J. Benton b a Department of Geology and Geophysics, University of Bucharest, Bd. N. Bălcescu 1, RO-010041 Bucharest, Romania b Department of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, UK article info abstract Article history: The Cretaceous was a special time in the evolution of terrestrial ecosystems, and yet the record from Europe Received 3 February 2010 in particular is patchy. This special issue brings together results of multidisciplinary investigations on the Received in revised form 4 May 2010 Late Cretaceous Haţeg area in southwestern Romania, and its continental fossil assemblage, with the aim of Accepted 25 May 2010 exploring an exceptional palaeoecosystem from the European Late Cretaceous. The Haţeg dinosaurs, which Available online 1 June 2010 seem unusually small, have become especially well known as some of the few latest Cretaceous dinosaurs from Europe, comparable with faunas from the south of France and Spain, and preserved at a time when Keywords: Cretaceous most of Europe was under the Chalk Seas. Eastern Europe then, at a time of exceptionally high sea level, was Tetrapods an archipelago of islands, some of them inhabited, but none so extraordinary as Haţeg. If Haţeg truly was an Dinosaurs island (and this is debated), the apparently small dinosaurs might well be dwarfs, as enunciated over Island dwarfing 100 years ago by the colourful Baron Franz Nopcsa, discoverer of the faunas.
    [Show full text]
  • Generality and Antiquity of the Island Rule Mark V
    Journal of Biogeography (J. Biogeogr.) (2013) 40, 1427–1439 SYNTHESIS Of mice and mammoths: generality and antiquity of the island rule Mark V. Lomolino1*, Alexandra A. van der Geer2, George A. Lyras2, Maria Rita Palombo3, Dov F. Sax4 and Roberto Rozzi3 1College of Environmental Science and ABSTRACT Forestry, State University of New York, Aim We assessed the generality of the island rule in a database comprising Syracuse, NY, 13210, USA, 2Netherlands 1593 populations of insular mammals (439 species, including 63 species of fos- Naturalis Biodiversity Center, Leiden, The Netherlands, 3Dipartimento di Scienze sil mammals), and tested whether observed patterns differed among taxonomic della Terra, Istituto di Geologia ambientale e and functional groups. Geoingegneria, Universita di Roma ‘La Location Islands world-wide. Sapienza’ and CNR, 00185, Rome, Italy, 4Department of Ecology and Evolutionary Methods We measured museum specimens (fossil mammals) and reviewed = Biology, Brown University, Providence, RI, the literature to compile a database of insular animal body size (Si mean 02912, USA mass of individuals from an insular population divided by that of individuals from an ancestral or mainland population, M). We used linear regressions to investigate the relationship between Si and M, and ANCOVA to compare trends among taxonomic and functional groups. Results Si was significantly and negatively related to the mass of the ancestral or mainland population across all mammals and within all orders of extant mammals analysed, and across palaeo-insular (considered separately) mammals as well. Insular body size was significantly smaller for bats and insectivores than for the other orders studied here, but significantly larger for mammals that utilized aquatic prey than for those restricted to terrestrial prey.
    [Show full text]
  • Insular Dwarfism in Canids on Java (Indonesia) and Its Implication for the Environment of Homo Erectus During the Early and Earl
    Palaeogeography, Palaeoclimatology, Palaeoecology xxx (xxxx) xxx–xxx Contents lists available at ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo Insular dwarfism in canids on Java (Indonesia) and its implication for the environment of Homo erectus during the Early and earliest Middle Pleistocene ⁎ Alexandra A.E. van der Geera, , George A. Lyrasb, Rebekka Volmerc a Naturalis Biodiversity Center, PO Box 9517, 2300 RA Leiden, the Netherlands b Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, Zografou, Greece c University of the Philippines, Diliman, Archaeological Studies Program, 1101 Quezon City, Philippines ARTICLE INFO ABSTRACT Keywords: Several canid fossils, which were originally discovered and described in the early 20th century, are known from Carnivore guild Early and earliest Middle Pleistocene of Java (Indonesia). Here we revise the taxonomy and relative age of the Island dwarfism Javanese canid fossils in light of recent developments in the taxonomy and phylogeny of Canidae, and new Mececyon insights in the evolution of island mammals. Results show that Cuon was absent during the Early and earliest Megacyon Middle Pleistocene while the large-sized Xenocyon (previously Megacyon) was present in the Early Pleistocene Trinil H.K. and replaced by the small-sized Xenocyon (previously Mececyon) during the earliest Middle Pleistocene. The Xenocyon latter is probably an anagenetic dwarf derived from the larger form of the preceding period. The change in body size of Xenocyon on Java over time is likely the effect of increased competition within the carnivore guild within the restricted boundaries of the island. Simultaneously with a pronounced body size shift, a dietary shift from large-sized prey to much smaller prey must have taken place in order to meet energetic constraints.
    [Show full text]
  • Insular Gigantism and Dwarfism in a Snake, Adaptive Response Or
    CORE Metadata, citation and similar papers at core.ac.uk Provided by Nature Precedings 1 Insular gigantism and dwarfism in a snake, adaptive response or spandrel to selection on gape size? Shawn E. Vincent1, Matthew C. Brandley2, Takeo Kuriyama3, Akira Mori4, Anthony Herrel5 & Masami Hasegawa3 1Department of Natural, Information, and Mathematical Sciences, Indiana University Kokomo, Kokomo, IN 46902, USA, 2 Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520-8105 USA, 3Department of Biology, Faculty of Science, Toho University, Funabashi City, Chiba, 274-8510, Japan, 4Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan, 5UMR 7179 C.N.R.S/M.N.H.N., Departement d'Ecologie et de Gestion de la Biodiversite, 57 rue Cuvier, Case postale 55, 75231, Paris Cedex 5, FranceDepartment of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520-8105 USA In biology, spandrels are phenotypic traits that evolve through their underlying developmental, genetic, and/or structural links to another trait under selection1, 2, 3. Despite the importance of the concept of spandrels in biology, empirical examples of spandrels are exceedingly rare at the organismal level2, 3. Here we test whether body size evolution in insular populations of a snake (Elaphe quadrivirgata) is the result of an adaptive response to differences in available prey, or the result of a non- adaptive spandrel resulting from selection on gape size. In contrast to previous hypotheses, Mantel tests show that body size does not coevolve with diet. However, gape size tightly matches diet (birds vs. lizards) across populations, even after controlling for the effects of body size, genetic, and geographic distance.
    [Show full text]
  • Dwarf Elephants on Mediterranean Islands: a Natural Experiment in Parallel Evolution
    Dwarf elephants on Mediterranean islands: A natural experiment in parallel evolution Volume 1 of 2 by Victoria Louise Herridge Department of Genetics, Evolution and Environment University College London A thesis submitted for the fulfillment of the Degree of Doctor of Philosophy University College London, 2010 1 I, Victoria Louise Herridge, confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. Signed: Date: 2 Abstract Mediterranean dwarf elephants represent some of the most striking examples of phyletic body- size change observed in mammals and are emblematic of the ‘island rule’, where small mammals become larger and large mammals dwarf on islands. The repeated dwarfing of mainland elephant taxa (Palaeoloxodon antiquus and Mammuthus meridionalis) on Mediterranean islands provide a ‘natural experiment’ in parallel evolution, and a unique opportunity to investigate the causes, correlates and mechanisms of island evolution and body-size change. This thesis provides the first pan-Mediterranean study that incorporates taxonomic and allometric approaches to the evolution of dwarf elephants, establishing a framework for the investigation of parallel evolution and key morphological correlates of insular dwarfism. I show that insular dwarfism has evolved independently in Mediterranean elephants at least six times, resulting in at least seven dwarf species. These species group into three, broad size-classes: ‘small- sized’ (P. falconeri, P. cypriotes and M. creticus), ‘medium-sized’ (P. mnaidriensis and P. tiliensis) and ‘large-sized’ (Palaeoloxodon sp. nov. and ‘P. antiquus’ from Crete). Size-shape similarities between independent lineages from the east and central Mediterranean indicate that homoplasy is likely among similar-sized taxa, with implications for the existence of meta-taxa.
    [Show full text]
  • U·M·I University Microfilms International a Bell & Howell Information Company 300 North Zeeb Road
    INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copysubmitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand corner and continuing from left to right in equal sectionswith small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back of the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6" x 9" black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. U·M·I University Microfilms International A Bell & Howell Information Company 300 North Zeeb Road. Ann Arbor. M148106-1346 USA 313:761-4700 800/521·0600 Order Number 9325033 Character release in the endangered Hawai'ian hoary bat, Lasiurus einereus semotus Jacobs, David Steve, Ph.D. University of Hawaii, 1993 Copyright @1993 by Jacobs, David Steve.
    [Show full text]
  • 'Island Rule' Apply to Birds?
    Lincoln University Digital Thesis Copyright Statement The digital copy of this thesis is protected by the Copyright Act 1994 (New Zealand). This thesis may be consulted by you, provided you comply with the provisions of the Act and the following conditions of use: you will use the copy only for the purposes of research or private study you will recognise the author's right to be identified as the author of the thesis and due acknowledgement will be made to the author where appropriate you will obtain the author's permission before publishing any material from the thesis. Does the ‘island rule’ apply to birds? An analysis of morphological variation between insular and mainland birds from the Australian, New Zealand and Antarctic region A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science (Conservation and Ecology) at Lincoln University by Elisa Diana Ruiz Ramos Lincoln University 2014 Abstract of a thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science (Conservation and Ecology) Abstract Does the ‘island rule’ apply to birds? An analysis of morphological variation between insular and mainland birds from the Australian, New Zealand and Antarctic region by Elisa Diana Ruiz Ramos The ‘island rule’ states that large animals become smaller and small animals become larger on islands. Morphological shifts on islands have been generalized for all vertebrates as a strategy to better exploit limited resources in constrained areas with low interspecific competition and predation pressures. In the case of birds, most of the studies that validate this rule have focused on passerines, and it is unclear about whether the rule applies to other Orders.
    [Show full text]
  • Body Size of Insular Carnivores: Little Support for the Island Rule. Author(S): Shai Meiri, Tamar Dayan, and Daniel Simberloff Source: the American Naturalist, Vol
    The University of Chicago Body Size of Insular Carnivores: Little Support for the Island Rule. Author(s): Shai Meiri, Tamar Dayan, and Daniel Simberloff Source: The American Naturalist, Vol. 163, No. 3 (March 2004), pp. 469-479 Published by: The University of Chicago Press for The American Society of Naturalists Stable URL: http://www.jstor.org/stable/10.1086/382229 . Accessed: 15/04/2013 15:37 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. The University of Chicago Press, The American Society of Naturalists, The University of Chicago are collaborating with JSTOR to digitize, preserve and extend access to The American Naturalist. http://www.jstor.org This content downloaded from 129.11.21.2 on Mon, 15 Apr 2013 15:37:08 PM All use subject to JSTOR Terms and Conditions vol. 163, no. 3 the american naturalist march 2004 ൴ Body Size of Insular Carnivores: Little Support for the Island Rule Shai Meiri,1,* Tamar Dayan,1,† and Daniel Simberloff 2,‡ 1. Department of Zoology, Tel Aviv University, Tel Aviv 69978, introduce exotic species) make islands an excellent arena Israel; for evolutionary research. 2. Department of Ecology and Evolutionary Biology, University of Among the most pronounced microevolutionary Tennessee, Knoxville, Tennessee 37996 changes occurring on islands are changes in body size.
    [Show full text]
  • Efekt Lilipuci – Typy, Przyczyny I Znaczenie Dla Organizmów Znajdujących Się Pod Działaniem Niekorzystnych Czynników Środowiska
    Tom 67 2018 Numer 2 (319) Strony 263–273 KRZYSZTOF ROMAN BROM, MARIUSZ ANDRZEJ SALAMON Katedra Paleontologii i Stratygrafii Wydział Nauk o Ziemi Uniwersytet Śląski w Katowicach Będzińska 60, 41-200 Sosnowiec WNoZ UŚ – Centrum Studiów Polarnych KNOW (Krajowy Naukowy Ośrodek Wiodący) Będzińska 60, 41-200 Sosnowiec Email: [email protected] [email protected] EFEKT LILIPUCI – TYPY, PRZYCZYNY I ZNACZENIE DLA ORGANIZMÓW ZNAJDUJĄCYCH SIĘ POD DZIAŁANIEM NIEKORZYSTNYCH CZYNNIKÓW ŚRODOWISKA WPROWADZENIE morfologię, funkcje życiowe i ekologię (TWIT- CHEtt 2006, 2007; HARRIES i KNORR 2009; Rozmiar ciała organizmu jest jedną z HUANG i współaut. 2010). Przykładami po- kluczowych cech, mającą decydujący wpływ znanych już efektów fizjologicznych jest na jego funkcjonowanie. Ujawnia się on pod ujemna korelacja masy ciała kręgowca z postacią różnych efektów metabolicznych, fi- częstotliwością bicia jego serca lub ruchów zjologicznych, rozrodczych, behawioralnych i oddechowych. Efekty ekologiczne objawiają ekologicznych (BLANCKENHORN 2000, HARRIES się np. jako dodatnia korelacja masy ciała i KNORR 2009, HUANG i współaut. 2010). Do- z wielkością zasięgu terytorialnego danego datkowo, jest to parametr, który zazwyczaj z gatunku oraz negatywna korelacja wielko- łatwością może zostać oszacowany, zarówno ści z gęstością populacji, występującej na w przypadku organizmów współczesnych, danym obszarze o danym czasie. Natomiast jak i kopalnych. Daje to dobrą aproksyma- przykładem efektów rozrodczych jest dodat- cję do analiz trendów wielkościowych orga- nia korelacja masy ciała z długością trwania nizmów w czasie, dlatego też publikuje się ciąży i inkubacji. Warto też wspomnieć, że liczne prace poświęcone zmianom wielkości im większy rozmiar, tym zazwyczaj dłuższy ciała wielu grup zwierząt w różnych inter- czas życia organizmu (patrz fig. 1 w HARRIES wałach czasowych (HARRIES i KNORR 2009, i KNORR 2009).
    [Show full text]
  • Dietary Reconstruction of Pygmy Mammoths from Santa Rosa Island of California
    Quaternary International xxx (2015) 1e14 Contents lists available at ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint Dietary reconstruction of pygmy mammoths from Santa Rosa Island of California * Gina M. Semprebon a, , Florent Rivals b, c, d, Julia M. Fahlke e, William J. Sanders f, Adrian M. Lister g, Ursula B. Gohlich€ h a Bay Path University, Longmeadow, MA, USA b Institucio Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain c Institut Catala de Paleoecologia Humana i Evolucio Social (IPHES), Tarragona, Spain d Area de Prehistoria, Universitat Rovira i Virgili (URV), Tarragona, Spain e Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitatsforschung,€ Berlin, Germany f Museum of Paleontology and Department of Anthropology, University of Michigan, MI, USA g Natural History Museum, London, UK h Natural History Museum of Vienna, Vienna, Austria article info abstract Article history: Microwear analyses have proven to be reliable for elucidating dietary differences in taxa with similar Available online xxx gross tooth morphologies. We analyzed enamel microwear of a large sample of Channel Island pygmy mammoth (Mammuthus exilis) molars from Santa Rosa Island, California and compared our results to Keywords: those of extant proboscideans, extant ungulates, and mainland fossil mammoths and mastodons from Island Rule North America and Europe. Our results show a distinct narrowing in mammoth dietary niche space after Niche occupation mainland mammoths colonized Santa Rosa as M. exilis became more specialized on browsing on leaves Proboscidea and twigs than the Columbian mammoth and modern elephant pattern of switching more between Tooth microwear Paleodiet browse and grass. Scratch numbers and scratch width scores support this interpretation as does the Pleistocene vegetation history of Santa Rosa Island whereby extensive conifer forests were available during the last glacial when M.
    [Show full text]