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Turtles: a cause for wonder, a cause for concern Thomas Akre Longwood University Farmville, VA

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The Tortoise and the Hare

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Turtles: a cause for wonder "Because they are still living, turtles are commonplace objects to us: were they entirely extinct, their shells the most remarkable defensive armor ever assumed by a tetrapod would be a cause for wonder." Alfred Sherwood Romer (18941973)

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Remarkable Defensive Armor E. S. Gaffney.

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Survivors in Armor Turtles (Order Testudines) are a unique (monophyletic) and highly divergent lineage They have existed nearly unchanged for at least 210 million years and survived the last great mass extinction 65 mya

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Survivors in Armor Millions of years agoThousands of Genera All Genera Well-defined Genera Mass Extinctions Triassic

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Survivors in Armor

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Millions of years agoThousands of Genera All Genera Well-defined Genera Mass Extinctions Cretaceous K-T

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Survivors in Armor

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Turtles in the Tree of Life Laurin & Gauthier 2009

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Turtle Relatives - Procolophonids Nycteroleter D. Bogdanov

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Turtle Relatives - Pareiasaurs E. Karkemish

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Turtles in the Tree of Life Modesto & Anderson 2004

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Turtle Relatives - Plesiosaurs Thalassiodracon hawkinsi N. Tamura

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The First Turtle? Li et al. 2008 Odontochelys semitestacea M. Donnelly

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The Earliest Turtles Li et al. 2008 C. Houck Proganochelys quenstedti

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The Turtle Tree of Life Joyce & Gauthier 2004 Odontochelys

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Tortoise and Freshwater Turtle Species Richness by 12100 km 2 Grid Species Richness

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The Side-Neck Turtles Gaffney and Meylan 1988

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How to Protect Your Neck Pleurodire F. Ippolito. Cryptodire

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The Side-Neck Turtles Pleurodires

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Tortoise and Freshwater Turtle Mean Root Distance by 12100 km 2 Grid Global Diversification

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Renous et al. 2008

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Meiolania: the Horned Turtle Gaffney and Meylan 1988

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Meiolania: Survivors in Armor Meiolania platyceps C. Houck F. Ippolito.

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Oceanic Voyages Gerlach et al. 2006

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So what is a turtle and what does it mean to be a turtle? In general, turtles have a suite of co-evolved life history characteristics that make them vulnerable to the effects of human encroachment Life history theory and evidence from long- term population studies suggest that turtles live so long because they are bet-hedgers; they have adapted to environments with unpredictable juvenile survivorship

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General Model of Turtle Life-History Traits Low nest (clutch) survivorshipLow nest (clutch) survivorship Low, but variable juvenile survivorshipLow, but variable juvenile survivorship Delayed sexual maturity (430 yrs)Delayed sexual maturity (430 yrs) At a certain size the shell confers protection that leads to high adult survivorship (often > 95%)At a certain size the shell confers protection that leads to high adult survivorship (often > 95%) Low annual reproductive output (fecundity)Low annual reproductive output (fecundity) Repeated reproductive cycles (extreme iteroparity)Repeated reproductive cycles (extreme iteroparity) Long life-span (mean max. from 15200 yrs)Long life-span (mean max. from 15200 yrs) Reduced or non-existent senescenceReduced or non-existent senescence

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Delayed Maturity A. Teti Glyptemys muhlenbergii Loxodonta africana

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The Whale in the Turtle Dermochelys coriacea C. Safina

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Mammalian Bone Growth Wyneken et al. 2008

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Giant Turtles R. Somma Stupendemys geographicus F. A. Lucas Archelon ischryos

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Survival

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The Tongue of the Turtle Heiss et al. 2010

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The Fish in the Turtle

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Feeding

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A Buffer Against the Cold

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Temperature Dependent Sex Determination and Female Choice Chrysemys picta M. JonesM. Marchand

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Nest Site Selection & Diapause Cann 1998

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Diapause and Aestivation

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Longevity

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Reproduction & Longevity Indeterminant Growth and Experience Reproductive output, Nest Success & Hatchling survivorship Cost of reproduction

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Turtles: a cause for concern commonplace objects were they entirely extinct "Because they are still living, turtles are commonplace objects to us: were they entirely extinct, their shells the most remarkable defensive armor ever assumed by a tetrapod would be a cause for wonder." Alfred Sherwood Romer (18941973)

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There is a Global Turtle Survival Crisis Habitat Loss Unsustainable Use Disease

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Global Turtle Survival Crisis Invasive species Global Climate Change Pollution

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Primary feeder markets of turtle imports into China have now reached into India, New Guinea, Africa, and the United India, New Guinea, Africa, and the UnitedStates

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Nearly half (42%) of the worlds tortoise and freshwater turtle species are threatened with extinction At least 70 species ( 25%) are poised on the brink of extinction

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Discoveries, rediscoveries, and elevations

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Turtle Services They occupy a diverse array of ecological niches and many species are considered to be critical components of the ecosystems they inhabit M. Dorcas D. Scott

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R. Masroor

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Turtle Symbols

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Global Species Richness and Turtle Hotspots Tortoise and Freshwater Turtle Species Richness by 12100 km 2 Grid

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Turtle Hotspots and Priority Areas Ganges-Brahmaputra Basin of India and Bangladesh

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The Human Footprint

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58 species of five families in North America Turtle Priority Areas

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The Tortoise and the Hare

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Thank you

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