Photosynthetic rates of seagrasses have until recently been measured a s gas exchange of chamber-enclosed leaves mainly in the laboratory, and in situ measurements under natural conditions are scarce. In this work we explore the possibility of rneasunng such rates by pulse amplitude modulated (PAM) fluorometry, using a newly developed underwater device. This was done by first comparing photosynthetic O2 evolution (net photosynthesis corrected for dark respiration) with rates of electron transport (ETR) derived from fluorescen.ce measurements of the effective quantum yield of photosystem I1 multiplied with the estlnlated photon flux of photosynthetic active radiation absorbed by this photosystem. In the field, ETRs were then measured both as rapid light curves (RLCs) and by in situ point measurements under ambient light during the day. Photosynthetic O2 volution showed a linear relationship with ETR within a range of irradiances for the Mediterranean seagrass Cymodocea nodosa, while the tropical Halophila stipulacea and a temperate intertidal population of Zostera marina exhibited decreasing O2 evolution rates relative to ETRs at high lrradiances. These differences are likely due to photorespiration, w h~c h is absent in C. nodosa. The molar ratio between photosynthetic O2 evolution and ETR within the range of their linear relationship was found to be 0.3 for C. nodosa, which is close to the theoretical stoichiometric ratio of 0.25, but was higher and lower for 2. manna and H. stjpulacea, respectively. Point measurements of ETR in the field showed good agreements wlth rates derived from RLCs for H. stipulacea and Z. marina, but values varied greatly between replicate measurements for C. nodosa a t high irradiances. It is speculated that this variation was partly due to lightflecks caused by waves in the shallow water where these measurements were done. In all, this work shows that PAM fluorometry can efficiently yield photosynthetic rates for seagrasses in the laboratory, without the typical lag experienced by O2 electrodes, a s well a s in situ under natural conditions which are not disturbed by enclosures.

Co‐occurrence of species of various geographical ranges is important to correct endemism evaluation. This co‐occurrence is shown as non‐hazardous. Influence of area size on species richness is assumed to be different with respect to endemic and non‐endemic species. The territory of Israel and Sinai is subdivided into twenty biotic provinces. We segregated three hundred and twenty‐five tenebrionid species inhabiting this territory into endemic, regional and ubiquitous species. Regression of the number of endemic species on the number of regional species is non‐linear. Two distinct regression lines correspond to hot and cool areas. The number of ubiquitous species depends positively on numbers of both endemic and regional species, and negatively on their product. Ubiquitous species are predominantly synanthropic, and inability to tolerate competition with other tenebrionids is assumed as the basis of numerical relationships with other species. Correlation between numbers of endemic and non‐endemic species of bird and mammal and size of area is analysed at the broad geographical scale. Relationships between area size evaluation and the numbers of endemic and non‐endemic species are always different. The square root of the area km2 is always more important in species richness determination than area itself. This variable is a linear characteristic of the area and its significance is discussed. Possible ecological interactions between species of various geographical ranges are also considered. A new method of evaluation of the level of faunal endemism is proposed.

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Aim To find out how common the earlier explored regularity is in numerical relationships among co-occurring species with various zoogeographical rank.Location The distribution of 284 species of Scarabaeoidea beetles in 20 biotic provinces of Israel and the Sinai Peninsula is considered. This Eastern Mediterranean territory is a part of the Levant area.Methods All species are allocated to one of three groups with different zoogeographical rank. These are the Levantine endemics (E), Regional (R) and Ubiquitous (U) species. Relationships among the numbers of species of each group were analysed with the use of multiple and ordinary regression. Similarity between faunas of resulting sets of provinces was analysed using the of chi-square test. ResultsThe numbers of E-and R-species in each province are statistically independent, while the number of U-species increases linearly with an increase in the E-and/or R-species number. Two linear regressions appear in the coordinates: ln (E + 1) -R. These regressions unify nine and seven provinces, respectively. The faunas of two sets of provinces differed significantly. Two fringe provinces, which were present within the territory considered only by small parts of their respective zoogeographical units, as well as two provinces with heavily destroyed habitats, fall out of the regression lines. The number of E-species increases in a south-north direction. The area of maximum diversity is assumed to be somewhat north of the Israeli state border. Success of the invading E-species is discussed from the standpoint of Van Valen's (1973) Red Queen Theory. Main conclusionsSpecies persisting together are not selected by chance. In our case, three zoogeographical ranks correspond to three grades of species' ranges. Different ranges are assumed to have different species' fitness. The present faunas have formed in the two sets of provinces in similar but independent ways.

The analysis presents earthworm distribution in eight designated tectonic units (C-Cyprus, EP-East Pondites, ET-East Taurus block, Sc-Sakarya continent, Kb-Kırşehir block, L-the Levant, TM-Taurus-Menderes block, WP-West Pondites) in the East Mediterranean region (EM). It represents a full list of earthworm species (N = 81) of the region and reveals significant faunal similarities between Sc ? WP, and between Kb ? TM. The new Sc ? WP unit is characterized by the presence of archaic (Spermophorodrilus) as well as modern earthworm fauna. In contrast, the second newly established Kb ? TM unit is characterized by poorly presented earthworm autochthonous fauna and by a lack of endemic species. The analysis done on the species list (N = 73) representing the autochthonous family Lumbricidae showed statistically supported separation of L and EP between themselves and from other designated units. The Levant, part of the Arabian tectonic plate, is characterized by a high level of endemism in ancient (Healyella) and modern (Dendrobaena, Perelia) genera, and by the lack of archaic genera. The EP harbors unique species representing archaic (Eophila), ancient (Healyella), and modern (Allolobophora, Aporrectodea, Dendrobaena and Eisenia) earthworm genera in the EM. The analysis also indicates origin of earthworm fauna in TM and faunistic

Abstract:The richness of endemic species is often recognized as an indication of the distinctiveness of certain local faunas and is used for the definition of conservation hotspots as well. Faunas of different animal taxa were considered in sets of contiguous geographical units. Comparing the faunas of different units in one set, we found an exponential increase in the number of endemics when plotted against the number of non-endemics. A model of independent stochastic population dynamics under the control of environmental oscillations produces random fluctuations in the ranges of species. Ranges of endemic species are supposedly narrower than ranges of co-occurring non-endemic species. In such a case, the flow of a random process leads to an exponential relationship between numbers of co-occurring endemic and non-endemic species. This process also produces an apparent positive correlation between total species number and the percentage of endemics.

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