The implications of palaeontological evidence for theories of ecological communities and species richness

Abstract Palaeontological evidence raises several questions that relate to current explanations of ecological communities, to the classification of communities and to interpretations of species richness. The first question relates to the stability of species detected in the fossil record. Coupled with that is the issue of incidental association of species on the same trophic level through differential effects of climatic change on the different species. Such observations are seen to support the ‘individualistic’ concept of communities. Recent statements about this concept leave unresolved questions about the acquisition of adaptation, and about the place of adaptation theory in theories of ecological communities and interpretations of ‘regional species richness’. At issue is whether there is justification for continuing to classify communities as a basis for understanding them. There is good reason to reject this approach for one in which questions about communities and ‘local’ and ‘regional’ species richness are replaced by more specific and basic questions about the relationship between adaptation, distribution and abundance, and ecological interactions. Some recent efforts to incorporate species theory into community theory fail because their basis remains the flawed concept of ‘local community’.     

Nephrotoxins and nephrotoxic species of the genus Penicillium Link

The present article is a review about the nephrotoxic species of Penicillium Link. Some chemical and toxicological information in connection with the nephrotoxins produced is presented. Besides, different opinions about the Penicillium nephrotoxic species classification are considered; particular attention is given to the toxin produced producing species linkage. A key for the determination of the nephrotoxic Penicillium species is presented. Generally, the taxa considered in the present work have been treated in several surveys. However, some diverse opinions about its delimitation, classification and toxin production still remain.     

南京地区耐寒常绿阔叶树种资源调查

南京地区地处亚热带北缘,是一些常绿阔叶树种自然分布的北界.通过对南京地区常绿阔叶树种的实地考察,表明南京地区有12种自然分布的常绿阔叶树种;目前园林上引种并已应用的有25种.另外,引种了109种能够露地栽培的常绿阔叶树种,其中乔木28种,灌木77种,藤本4种.可以认为南京地区是耐寒常绿阔叶树种引种分布的关键地区.     

广西大瑶山自然资源的特点及今后利用的方向

大瑶山是广西有名的大山,北纬23°40′—24°24′,东经109°50′—110°27′,面积约2080平方公里。 大瑶山起源于二迭纪,是一座古老的山体。大瑶山生物种类丰富多彩,区系植物213个科,2335种;陆栖脊椎动物69科,281种;昆虫176科,836种;森林植被四个植被型,34个群系。大瑶山生物地理成份复杂,植物区系有热带东南亚、东亚、北温带、旧世界热带和泛热带的成份;昆虫区系有东洋种、古北种和本地特有种。古老、孑遗和特有、珍稀种类不少,蕨类植物250种,裸子植物7科22种,木兰科4属16种,国家保护的珍稀植物有桫椤、白豆杉、福建柏、猪血木、大果木五加、伞花木、南华木、紫荆、金莲木等35种;珍稀动物有瑶山鳄蜥、猕猴、短尾猴、大鲵、山瑞、红腹角雉等12种。大瑶山具重要经济意义的种类较突出,如:灵香草、八角、玉桂、罗汉果等。因此,大瑶山是广西中部一个重要的生态系统;是广西重要的和理想的科学研究和教学之处;是广西非常重要的自然物种基地;是广西重要的木材和土特产基地。大瑶山今后主要是保护起来,建立自然保护区,同时,大力发展木材和土特产。     

How much do we know about the current extinction rate?

Since about J600, 486 animal species have been recorded extinct. This represents about 0.04% of all animal species so far described. In the same period, 600 plant species are known to have disappeared, about 0.25% of the total. These figures are much smaller than those of the Permian/ Triassic and Cretaceous/Tertiary mass extinctions. One might therefore conclude that at present life on earth is at comparatively little risk of extinction. However, there is a growing body of data to show that the converse is true.     

The number of species of rodent coccidia and of other protozoa

About 447 species of coccidia have been named from the 1687 living, known species of rodents; 207 host species, 92 host genera, and 15 host families are represented; this is about 12% of the known species of rodents. About 4600 species of apicomplexan protozoa have been named. Assuming that the same proportion of the total number of apicomplexan species has been named as of the coccidian species, there must actually be about 38,333 species of apicomplexan protozoa. There are 5.4 times as many protozoan genera as of apicomplexan genera. Assuming that the number of species in each genus is the same for all the protozoa as it is for the Apicomplexa, there may actually be 206,998 species of protozoa. This may be too conservative an estimate. Based on other criteria, an estimate of over 20 million species could be made.     

First report of Melittobia australica Girault in Europe and new record of M. acasta (Walker) for Italy

Melittobia acasta and Melittobia australica are newly recorded from Sicily, Italy, and the second species is reported in Europe for the first time. A short historical background about Melittobia parasitoid wasps, their hosts, and distribution, with emphasis in those two species is presented together with illustrations to facilitate their identification. Brief discussion about the presence and possible distribution of the species in Sicily is also included.     

Echinoids of the Pacific waters of Panama: status of knowledge and new records

This paper is primarily intended as a guide to researchers who wish to know what echinoid species are available in the Bay of Panama and in the Gulf of Chiriqui, how to recognize them, and what has been published about them up to 2004. Fifty seven species of echinoids have been reported in the literature as occurring in the Pacific waters of Panama, of which I have collected and examined 31, including two species, Caenopedina dìomedìae and Meoma frangibilis, that have hitherto only been mentioned in the literature from single type specimens. For the 31 species I was able to examine, I list the localities in which they were found, my impression as to their relative abundance, the characters that distinguish them, and what is known about their biology and evolution. Not surprisingly, most available information concerns abundant shallow water species, while little is known about deep water, rare, or infaunal species.     

Reproduction of two species of congeneric fruit bats (Cynopterus) in Brunei, Borneo

In summary, the reproductive cycles of C. minutas and C. brachyotis are shown in Fig. 12. Reproduction of both species is seasonal and continuous bimodal polyoestry, however, reproduction of neither species is linked to rains nor the general season of flowering/fruiting of trees.
Adult females of both species produce 2 litters/yr, 1 neonate/birth. Within each species, the females are in reproductive synchrony, with young born in two distinct seasons (3–4 months each) of parturition 5–7 months apart, centring about the two seasons of less rain, which may correspond to the fruiting of certain species of trees (e.g. mangoes for C. brachyotis ). Each parturition is followed by postpartum oestrus. Gestation spans about 5–6 months, with embryonic development delayed or arrested in early stages. Both sexes of C. minutas (and probably also C. brachyotis ) attain sexual maturity at about 7 months, with females giving birth the first time at about 12 months.     

Interspecific abundance–occupancy relationships of British mammals and birds: is it possible to explain the residual variation?

Aim The majority of studies concerning positive interspecific abundance–occupancy relationships have used broad‐scale and microcosm data to test the occurrence and correlates of the relationship to determine which of the proposed mechanisms give rise to it. It has been argued recently that studying the residual variation about abundance–occupancy relationships is a more logical analysis and may yield faster progress in identifying the relative roles of the mechanisms. However, to date this approach has been largely unsuccessful. Here we test if fundamental species traits such as the status (native and introduced), habitat and trophic group of mammal and bird species may explain any of the residual variation about their respective abundance–occupancy relationships. Location The study used British mammal and bird species. Methods We tested if species traits explained any of the variation about abundance–occupancy relationships using linear regression techniques both treating species as independent data points for analysis and controlling for phylogenetic association. Results None of the species traits could explain any residual variation about the positive interspecific abundance–occupancy relationships of British mammals and birds. This applied both when treating species as independent data points and after controlling for phylogenetic association. Conclusions Given the lack of explanatory power of the species traits here and in other studies using this approach it seems that the variation about positive interspecific abundance–occupancy relationships is not explicable in a simple fashion. Predicting the likely influence of traits that are independent of phylogeny is also problematic. Therefore, the general utility of this approach and its future role in understanding the mechanisms causing positive interspecific abundance–occupancy relationships is doubtful.     

横断山区高等真菌物种多样性研究进展

中国西南横断山地区地形复杂、山陡谷深、生境多样,是真菌栖息、繁衍和分化的理想地区。国内外真菌学家们对该区的真菌早就给予过关注和研究,曾报道了该区真菌4000余种,约占我国已知真菌总种数的40%。然而,总的说来,人们对该区真菌物种多样性的了解还知之甚少。近十余年来,我们对该地区的真菌中的高等真菌部分进行了十余次野外考察和采集,共获得标本7000余份、分子材料4200余份、真菌及其生境照片1万余张,这是研究和认识该区真菌多样性不可或缺的第一手科学资料。通过对该区有关标本的研究,正式发表了2新属及50余新种;但还有大量新物种和一些新属有待进一步研究和描述。加强真菌多样性的研究,不仅具有重要的科学意义,同时为经济发展服务也具有重要的现实意义。     

滇西北香格里拉县大型真菌资源及其利用现状

香格里拉县（中旬县）位于云南省西北部,该区域内地形地貌复杂,海拔高差悬殊,兼有温带和寒温带高山气候类型。该区具有典型的温性、寒温性针叶林和寒温性常绿阔叶林以及针阔混交林,其中有不少是能与大型真菌形成共生关系的树种,如云南松（Pinus yunnanensis Franch．）、高山松（P．densata Mast．）、川滇高山栎（Quercus aquifolioides Rehd．etWils．）、灰背栎（Q．senescens Hand．-Mazz．）以及高山桦（Betula delavayi Franch．）和白桦（B．platyphylla Suk．）等。     

Diversity of germ layer and axis formation among mammals

The class mammalia is composed of approximately 4800 extant species. This class is divided into three subclasses, the prototheria (monotremes), metatheria (marsupials), and eutheria. Surprisingly, there is relatively little knowledge about germ layer and axis formation in mammalian species. Most knowledge about these embryonic processes has been obtained from one species, the mouse, Mus musculus. Here we discuss major variations in germ layer and axis formation among mammals. We suggest that more studies of embryonic development in diverse mammalian species are required for an understanding of germ layer and axis formation to provide insights into human biology and disease.     

On the meanings of nestedness: back to the basics

The ecological concepts of nestedness and β‐diversity first appeared more than five decades ago, but there is still controversy over their precise meaning and application. Here, we focus on the concept of nestedness, the ordered loss of species along environmental or ecological gradients. Because there is no species replacement if the distribution of species among a number of sites is perfectly nested, some studies have defined nestedness as the inverse of species turnover. We argue that such a redefinition relies on a misinterpretation of the original concept of nestedness as the inverse of species replacement. Such a narrow interpretation might result in misleading conclusions about the mechanisms regulating species distribution patterns. We argue, in particular, that any quantification of nestedness must be as explicit as possible about the gradient to be analyzed.     

First phylogenetic and biogeographical study of the southern bluebells (Wahlenbergia, Campanulaceae)

Wahlenbergia is a largely southern hemisphere genus of at least 260 species; within Campanulaceae only Campanula is larger. This first phylogeny of Wahlenbergia was reconstructed using about 20% of the 260 species in the genus based on the nuclear ribosomal ITS marker and the chloroplast trnL-F marker with samples from South Africa, Europe, Australia and New Zealand. Wahlenbergia was confirmed to be non-monophyletic, though most of the species form a clade. Our tree topology and date estimates indicate that Wahlenbergia diverged in South Africa about 29.6 mya, then dispersed to Australasia about 4.8 mya, thus indicating the radiation of Wahlenbergia occurred relatively recently. Radiations occurred in both of these main centres; there are currently about 170 species in South Africa and 45 species and subspecies in Australasia. New Zealand species comprise two clades, both rooted within the Australasian clade. We thus propose two dispersals from Australia to New Zealand, one leading to a radiation of species with the rhizomatous herbaceous growth form ca. 1.6 mya, and the other leading to a radiation of species with the radicate growth form 0.7 mya. Dispersals from Australia to New Zealand match the expected direction, following the west wind drift and ocean currents. The herbaceous growth form was shown to be ancestral for the genus as a whole, and polyploidy has been a mechanism of the evolution of the genus in Australasia.     

广东内伶仃岛猕猴食性及食源植物分析

论文对内伶仃岛猕猴(Macaca mulatta)的植物食性进行了全面调查,并测定了食源植物适食部分的比重。研究结果表明:(1)猕猴食源植物约200种,以叶食性、果食性最为丰富;(2)猕猴的活动区域以阔叶林、灌木林等植被类型为主;(3)食源植物以热带亚热带成分为主,与栖息地植被组成特征相适应;(4)内伶仃岛猕猴种群发展的容纳量最适为820～1640只(平均1230只),而以743～1485只(平均1114只)最为合适,其总食量约相当于适食性优质植物资源总蕴藏量的10%～20%。     

Out of Tanganyika: Genesis, explosive speciation, key-innovations and phylogeography of the haplochromine cichlid fishes

Background  

The adaptive radiations of cichlid fishes in East Africa are well known for their spectacular diversity and their astonishingly fast rates of speciation. About 80% of all 2,500 cichlid species in East Africa, and virtually all cichlid species from Lakes Victoria (~500 species) and Malawi (~1,000 species) are haplochromines. Here, we present the most extensive phylogenetic and phylogeographic analysis so far that includes about 100 species and is based on about 2,000 bp of the mitochondrial DNA.     

武陵山区蕨类植物研究

武陵山区蕨类植物资源丰富,现知有644种(包括变种),分属116属, 46科;蕨类区系属热带-亚热带山地类型;属的地理成份有12种类型,与日本、印度-马来西亚有密切关系;武陵山区蕨类区系属我国西南区系,与华中华东区关系密切,华南、华北区次之;蕨类垂直分布分四带。     

中国菊属一新变种

报道了中国菊属(Chrysanthemum)一新变种——阔叶毛华菊(Chrysanthemum vestitum(Hem sl.)Stapf.var.latifolium J.Zhou et J.Y.Chen)。本变种与模式变种的区别在于直立生长,并且较多分枝,叶较狭,卵状披针形或匙形,长4~6 cm,宽2~3 cm。花序直径较原种为小,约3.5~4.5 cm。主要分布于湖北宜昌、河南伏牛山山脉。抗旱性较原变种强。而主要原产于安徽西部大别山麓之模式变种则铺散生长,较少分枝,叶圆形、卵圆形,长4~7cm,宽3~5 cm。花序直径较大,约4.5~5.0 cm。     

A Classification Synopsis of the Genus Dryopteris from Yunnan

The genus Dryopteris of the Dryopteridaceae is one of the largest genera in pteridophytes, which contains about 300 species and is distributed throughout the world. There are about 200 species of this genus in China, of which at least 88 are present in Yunnan. In this paper, the author presents a classification synopsis of the genus Dryopteris. Subg. I Pycnopteris (T. Moore )Ching 1 species Subg. II. Dryopteris Sect. 1. Hirtipedes Fraser-Jenkins 19 species Sect. 2. Pandae Fraser-Jenkins 1 species Sect. 3. Fibrillosae Ching 18 species Sect. 4. Chrysocomae S. G. Lu 7 species Sect. 5. Caespitosae S.G.Lu 5 species Sect. 6. Pallidae Fraser- Jenkins 10 species Sect. 7. Marginatae Fraser-Jenkins 7 species Sect. 8. Splendentes Fraser- Jenkins 2 species Sect. 9. Purpurascentes Fraser- Jenkins 1 species Sect. 10. Nephrocystis H. I tô 3 species Subg. llI. Erythrovariae (H. I tô ) Fraser-Jenkins, emend. S.G. Lu Sect. 11. Erythrovariae 11 species Sect. 12. Variae Fraser- Jenkins 3 species A key to these groups is given and all the species are enumerated in the pres- ent paper.