AMERICAN MUSEUM OF NATURAL HISTORY EVOLUTION OF THE SS SN Yj if Ali Ye :;; DNS WY) wn oh ‘sill GAs i ia hike . 4 it ou Ds i \ \ “ec A mn SS | By W. D. MATTHEW AND S. H. CHUBB NO. 36 OF THE GUIDE LEAFLET SERIES—APRIL, 1921 f ij Yh, a = \ \ ‘\ | lt PaN \\\ \ i 1h aA ! a \" \\ ‘ aan
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SKELETON OF HORSE AND MAN Mounted for comparative study. Gift of the late William C. Whitney to the American MuseumofNaturalHistory
EVOLUTION OF THE HORSE IN TWO PARTS feo) ETON OF THE HORSE IN NATURE BY W. D. MATTHEW THE HORSE UNDER DOMESTICATION: ITS ORIGIN AND THE STRUCTURE AND GROWTH OF THE TEETH BY = H. CHUBB GUIDE LEAFLET SERIES, No. 36 FOURTH EDITION, REVISED New York, Marcu, 1921 PUBLISHED BY THE MUSEUM
‘“* * * the general principles of the hypothesis of evolution lead to the conclusion that the horse must have been derived from some quadruped which possessed five complete digits on each foot; which had the bones of the forearm and of the leg complete and separate; and which possessed forty-four teeth, among which the crowns of the incisors and grinders had a simple structure; while the latter gradually increased in size from before backwards, at any rate in the anterior part of the series, and had short crowns.
And if the horse has been thus evolved, and the remains of the different stages of its evolution have been preserved, they ought to present us with a series of forms in which the number of the digits becomes reduced; the bones of the forearm and leg gradually take on the equine condition; and the form and arrangement of the teeth successively approximate to those which obtain in existing horses. Let us turn to the facts and see how far they fulfil these requirements of the doctrine of evolution.”
Huaxley. The Demenstrative Evidence of Evolution.
CONTENTS Part I. EvoLutTion or THE Horse In Nature PAGE Per 9 Fosstt Horses OF THE AGE OF MAN............ ee 12 SepeeeeNOGN IU 9TH FIOHOE.. ow Se ee ee ee wues 14 a ge ig Sc 14 NENTS he ho Svs cue cal’ Cbd nu dae udavburedagec 17 PRR Any AB Fe tise Si oe ck ee Weeds sate 22 RII ET yO ee Los ais oss apd oa wed wa Ge OD aw bee es 23 MEANING OF THE,CHANGE IN FEET AND TEETH.................-cececeee 26 SS 32 Peat, EVOLUTION IN OTHER RACES. .............-...0cc eee cceeeee 33 Part II. THe Horst UNDER DOMESTICATION De ae BIT DOMESTIC HORSE «2. oo. ence sos ep ci ere ee ee ee ea wee gee 39 COMPARISON OF THE SKELETON OF HORSE AND MAN..................22-05: 41 UTE ERE NOME retin US gO PN a. ee Gig BSc (09S eevee © Seas adhe Se ewe 41 DEVELOPMENT OF GREAT SIZE IN THE Drart HORSE.................... 3 MPTP ONIN eae ve eh ae NS ee en ee ww Op ad 43 NTE ROSES Ee gS pee ude dio oe ws alee Swe gh bok ok wa 44 RIE NLICS Ht PO Reet rn Say Be i nce ow bw ial 45 Preeti OW Tam HORSH 2.6 cS. lah. ye Bee be ee ee ees 4s (USS CESS Seg NSS 2 re ere ane 48 Wear and Compensating Movement of the Incisors............ 50 Perea On mbentectite <2. 2! wk tetrg ek 4 cle we eo glee eos 52 Me wannor ieckiotce: 2"... 72 eo ee SS bece si de eee ee be a bee es 54 Ertemolars and Molars of the Horse. ...2.2. 5.2... 06. eee en ees 54 Eeuptien ot the Teeth of the Horse. ....:....:.........-. 60 2 LES ENS gg ee ee 62 PRINCIPAL LITERATURE IN THE EVOLUTION OF THE HORSE ..... 64 Dn eR Alte CI a ana ee 67
LIST OF ILLUSTRATIONS PAGE Skeleton of Horse and Bian 403 o.7 65. -. 50 DS whee eo ee Frontispiece 1. Bvolution of the Horse 76.05 Seki h sins 2 3. A A ane eee 8 2. Evolution of the Fore Foot. Principal Stages......................... 10 3. Evolution of the Hind Foot. Principal Stages........................ 11 4. Upper Teeth; Hohappuad 5 oso oe eae ee 2 Ret ae ee 15 5. Upper Teeth, Orokipgiue. 04 npase eck So oe heen oe oe 16 6: Upper Teeth; Epihippuss | Cee rn 2k eye See 16 7. Upper Teeth, Mesohippua. i. /s< 2 ooo oor Ge ho Oe ee 17 8. Little Three-toed Horse (Mesohippus bairdi) and Four-toed Horse (Eohippus venticolus). 0 icons ds ict on nt ee eee 18 9. Skeleton of Three-toed Desert Horse (Hipparion whitneyi).............. 19 10. Upper Teeth, Parahippus.. 202)... Zahn cee ek eee 20 11. Upper Teeth, Merychipima. .5.5 22.0 See ieee oe eae oe eee 21 12. ‘Upper: Teeth, Htpparion.: 035.5. Aw ee eee ee ee eee 22 13.- Upper Teeth, Equus: ot. ..450.25 3S ee eee 23 14. Skeleton of Extinct American Horse (Equus scotti)..........0..0.0....... 24 15. Skeleton of Short-limbed Horse, Hippidium........................... 25 16. Geological and Geographical Range of Ancestors of Horse.............. 26 17. Tvolution of the Fore Leg. Principal Stages’. :.. 92s <0... eee 27 18. Evolution of the Hind Leg. Principal Stages.::.. 0)... . <>. ie 28 19, 20. Evolution of the Teéth® :... 20. {oes es at kes ) 29 21. Evolution of the Hind Foot of the Horse. .:....:......3. 2s. 2 2ee ee 31 22. Fore and Hind Feet. Three-toed Pseudo-horse....................... 33 23. Fore and Hind Feet. One-toed Pseudo-horse.......................-. 34 24. Evolution of the-Horse,.. .. 2.9... oc aes 2 ee 36, 37 25. Giant Draft Horse and Shetland Pony................... 0 38 26. Draft Horse Pulling Heavy Load (Skeleton).......................... 40 27.. Arabian ‘stallion “Nimr” (Skeleton)... >. . 2... 02? 2 eet ee 40 28. Draft Horse. Rear view showing action of pelvis and backbone......... 42 29. Famous American. Race Horse.“Sysonby” > .9o.7 2. i... 42 oe. eee eee 47 30. Incisor Teeth showing different degrees of specialization................ 49 31. Incisor Teeth showing wear and movement....................+-++4-- 49 o2. Designation of “Teeth. ooo tc cee a os ea ae ee 53 33. Wearing Surface of Upper Grinding Teeth....................-..--..--- 55 34; Sections af Upper Gemaerof Hotaé.. fn 0... oe So Sac ee eee 56 35. Lower Premolar of Horse................ Sua Pep Se i ee + ae 57 36. Deciduous Molar of Colt.......... ONCE ce Unt soe Se caee eae rnc 58 3/.. Dental Battery of Adult Horse. >...) 2. atgc.o Sea ee ie 59 38. .Dentrtaon’ of the Galt... S5e0: << 5.35 6k has ee eee 61