Animal Life in Palestine
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ANIMAL LIFE IN PALESTINE An introduction to the problems of animal ecology and zoogeograpby. BY F . S. BODENHEIMER Professor of Zoology, Hebrew University, Jerusalem ; Chief Entomologist, Agric. Exper. Sta., Rehoboth; Member of Scientific Council, International Institute of Agriculture, Rome; Membrum Academiae Leopoldinae Carolinae, Halle; Membre Correspondent de l'Academie Internationale d'Histoire des Sciences, Paris. To be obtained throu gh: L. MAYER, JERUSALEM, P.O.B. 932 . ..JERUSALEM 1 935 Ill. REPTILES AND AMPHIBIA. A. Zoo g e 0 g rap h y and E col 0 g y . - The zoogeography of the reptiles and amphibians does not show anything exceptional. The high percentage of aharo- indian forms among the reptiles simply indicates a rich development of the life of this family in deserts and predeserts. ince tropical animals are generally restricted to humid habitats, they are rather poorly represented amongst these lovers of arid habitats. Euro-Siberian elements are entirely lacking: I Total No. I Med. Sah. Ir. Tur. Trop. Eur. Hol. o! species Sind. Sib. Snakes I 33 I 12 ,5 13,0 6,0 1,5 - - Lizards I 37 I 12 ,5 15,5 7 2 - - Tortoises I 5 I 2,5 1 1,5 - - - Amphibians I 8 I 5,0 1,0 0,5 - 0,5 1 Total 83 32,5 30,5 15,0 3,5 0,5 1,0 I % 100,2 39,2 36,9 18,1 4,2 0,6 1,2 The semi-arid character of the country has a decidedly adverse influence on the amphibians and the few species which do occur (Sala mandra, Triton, Pelobates) are very rarely seen owing to their strictly nocturnal habits. Many of the species are of Irano-Turanian origin and have spread into Palestine only in a relatively recent period. All species of genera, such as Lacerta, Tropidonotus are good illustrations. Many of the Scincids and Agamids have the same origin. They are typical dominants of steppe environments and must have flourished during the late diluvial and the present alluvial period, but many of these species have formed local sub-species in the Eastern Mediterranean. The body temperature of the reptiles depends to a high degree upon that of the environment. The temperature of the lizard, in the shade, generally coincides with the temperature of its surroundings. A lizard's temperature in the sun on the other hand rises up to 400 C and higher, when the shade temperature, for example, is only 280 C. It utilizes the rays of the sun to raise its body temperature. Fig. 40 182 ANIMAL LIFE I PALEST! lE T VYi -. Vl'"W- .- irr". I I ,. 2 3 3 " 6 7 8 9 10 11 12 13 I~ Fig. 39. Sea onal and diurnal aClivity of Ophiso ps ehrellbergi (at right) and Testudo ibera (at lefl ). The data on T est udo from S. Ulitzki ). illu trates the e conditions, fairly well. From 11- 14 h the body tem perature of a tellio, in October, approache even 400 C, excepting fr om 11: 30- 12 :15 h when the lizard was in the shade, and registered exactly the temperature of it environment. The afternoon of that day was cloudy and windy and a a consequence, the body temperature dropped. During the cooler sea ons the reptilian activity is highest at noon , but many species lessen their activity or even interrupt it, in the noon hours, during the summer. In a long serie of experiment all Hardoun died when they were exposed to the direct ray of the sun for two hour at noon. The ame pecies is, however, frequently een in nature, during the noon hours. In our experiments, however, the maximal surface of the body was turned to the un, whereas, in nature, the body-axis of the lizar,d runs parallel to the direction of the sun-rays, which mean that it turns its minimal surface to the sun. In this way, it lower its body temperature by everal degrees a compared with the first posture. In the. activity experiments, lizards behaved as follows : Cold Hil!h S P e c i e s I Instanta- I Preference I torpor I activity neous death temperature Lacerta laevis I 8,5 I 33 ,S 44,8 0 C I 31 ,7 0 C Agama stellio 3,4 I 39,2 47 ,S 0 C I 33 ,4 0 C Ophisops ehl'enbergi I 3,5 I 36,S 44,0 0 C I 35 ,3 0 C I Gongyltfs ocellatus I 2,7 I 36,S I 44,8 0 C I Ptyodactylus syriacus I 5,5 I 35,S I 43 ,7 0 C I Gymnodactylus kotschyi I - I - I 44,S 0 C I Rana ridibunda I - 0,9 I - I 40,9 0 C Bufo vil'idis I 4,1 I 36,2 I 40,7 0 C I OUR REPTILES A D AMPHIBIA 183 A rise of the body temperature to about 45 0 C means i·nstan taneous death to these lizards. A slow normal activity begins at 17,50 C and a body temperature of 350 C is needed for full activity. These data: fully explain the activity behaviour of reptiles. ear Jerusalem the . /1111),..., 'JUJ """1~1i11 ?IJi1 nlIOJ!}r.JO BODY AND PREFERENCE T£NP£RATURE 0,. AGANA 5 TEl LlO . ..". ,:. ' ...., \,~ r, "N' O,,"t/(1 'Jnl'tIUill-..r .... .,. "-" "- , .........., .-.... '\ f • '- " .... , ... ..,,' \ ~ 6 . - - - - - ·· ·1 I t" ..-'.' _ ~ ~/ " j - ~" J b="':~~~:~~: :~ : J: __,,_ 11" 1" 12" " 1t"-IF -tF" *'j-I\ W C'" .. ;~:~(> lY4 l!..... 1(.. .. '6" Jf JoO 'C' ~ I! 6 )(.30- Ttl'""lIf'" '0# _~,,~ .()< M""I'M '"' ..... ~ ~'V . - -$:If/. ,, - -----05 .. ""'" 'J: --- Fig. 40. Body temperature of Agama stellio under the influence of normal sun radiation. At right above: The preference temperature of A . stellio. great activity of the Hardoun stops at 16 h in August, and at 12 h In October. It begins at 5 h in June and at 7 h in October. The preference temperature is at about 340 C, i. e. at the lower limit of high activity. Fig. 40 shows the preference reaction of a Stellio when it has the choice of a long series of temperatures. Reptiles are well adapted for li ving in arid conditions. Their skin has a thick corneous stratum. The glands of its skin are very restricted in number and consequently the evaporation is minimal. Much of the life history of our reptiles remains to be studied. The nuptials of most lizards seem to take place in the summer months, but their courtship has not been adequately observed. The seasons and numbers of ovipositions are absolutely unknown. In the Common Har doun they seem to be rather protracted. Oviposition begins not later than June/ July, but mature eggs are found in the females even at the begin ning of September. One can only guess at the length of the egg-stage 184 ANIMAL LIFE IN PALESTINE and the duration of the whole development. Most lizards probably mature in one year, while snakes and tortoises require several years. No true estivation or hibernation is known in the case of reptiles. Neverthe less, many species lie in their holes in a state of semi-torpor durina the coolest weeks of the rainy season. Often groups of from 6 to 20 and even more individuals may be found together. They immediately become active, when the sun's rays waken them. The real extent of this pseudo hibernation requires more detailed study. It depends upon external con ditions, only, and its length in the mountains differs from that near Jericho. The nocturnal geckoes have certain humidity requirements. Their skin contains many glands and its corneous layer is very thin. The amphibians are entirely dependent on the presence of water. All of them develop their tadpoles, there. Their main activity is during winter and spring. Bufo and Pelobates, whose tadpoles may be found as early as December, are the first to lay their eggs after the beginning of the rainy season. In January the tadpoles of Hyla are common and those of the Frog (Rana ridibullda) appear in February. The ewts oviposit from February and the Salamander probably also oviposits at the same time. The tadpoles of the Green Toad require two months for their development, in the winter, and six weeks, in the spring. They are still seen through the summer if conditions are favorable for breeding. In March/ April their long egg-chains are quite common and during the somewhat abnormal summer of 1932 eggs and tadpoles were observed as late as July, wherever fresh-water was still present. The arr. phi~ians are not protected against evaporation by a corneous layer of the skin, but rather by the presence of many mucus glands. In our Tree-frog the number of these glands is 25- 50% greater than in individuals from Central Europell). A higher degree of protection is necessary in our arid and hot climate and it is attained by an increased mucuous secretion. It tolerates the heat better when the air is humid. }t dies within one day when exposed to a ReI. Humidity of only 20%, after four days when exposed to 80ro R. H. and only after 63 days when exposed to 100% R. H. (without food)12). The protection by the mucus glands is sufficient to enable it to survive through the favorable conditions of the hot noon-hours, to which it is sometimes exposed, even in the summer. B. S D a k e s . - The common representative of the Blind Snakes (Typhlopidae) is the European Blind Worm (Typhlops vermicularis).