This issue is the proceeding of a symposium held at the 1998 Annual Meeting of the Ornithological Society of Japan, Kitakyushu City. Biochemical techniques have made remarkable progress and become a powerful tool in ornithology as well as in other fields of life science.An aim of the symposium is to review current situation of biochemical analysis in the fields of ornithology, such as systematics, population genetics, behavioral ecology, population ecology and conservation ecology.

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Advances in molecular techniques, particularly the development of DNA sequence determination, have led to an explosive increase in studies of avian phylogeny. To date, many of these studies have examined mitochondrial DNA (mtDNA) because it has many useful features for the study of the phylogeny of closely related taxa. Unfortunately, however, the use of mtDNA also has some problems since mitochondria are inherited maternally. Samples of blood, tissue, feather and even dried skin can be used as a source of DNA. DNA sequences are analysed in the order: extraction, amplification, sequence determination. Inferences about phylogenetic relationships from sequence data are made using an assortment of methods that include parsimony, maximum likelihood, and distance. The confidence levels of the resulting phylogenetic trees can be determined using statistical methods such as bootstrap. For the time being, it is not possible to delimit species solely on mtDNA information. There are many unsolved problems, and many fruitful areas for study in the phylogeny of Japanese birds. DNA analysis is a requisite method to solve these problems. Phylogenetic analysis using DNA sequencing will play a leading role in solving questions relating to avian evolution.

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The mitochondrial control region of the Hazel Grouse Bonasa bonasia was analyzed using 126 samples collected from Hokkaido, 11 samples from Magadan in Far East Russia and two samples from Bohemia in Europe. A total of 32 polymorphic sites were detected in the sequence data from 428 by in the left domain of the control region, defining 47 haplotypes. A phylogenetic tree using the 47 haplotypes and B. sewezowi as an outgroup showed that haplotypes of B. bonasia was not separated with a significant bootstrap value; and all the haplotypes belonged to a single continuous cluster.Network analysis with the 47 haplotypes indicated that most of these haplotypes were connected with l-substitution difference radiating from hypothetical node consisting of same haplotypes. It might suggest a large genetic expansion from these haplotypes in Hokkaido, or circum area in northern Asia, in a recent period, possibly during the last glaciation.
The geographical distribution of the haplotypes in Hokkaido populations are genetically overlapped except the southern population.However, the haplotype coexistence between Ishikari area and east Tokachi area, south Abashiri area and Nemuro area were remarkably low, suggesting that movements of the hazel grouse might be restricted by mountains higher than 1000 m. Haplotype diversities (h) larger than 0.8, suggested that a reasonable population size has been maintained through the history, though the population of the Hazel Grouse in Hokkaido had a rapid decline over the last 50 years.

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It has been widely suggested that inbreeding causes a loss of constitutional vigour and fertility in domestic livestock.Long-term field studies of pedigrees in avian populations have also revealed that inbreeding typically decreases the fitness of each individual, but may increase fitness under certain circumstances. The degree of inbreeding in a population depends on its geographical isolation and/or its demographic situation.Under the restricting condition of dispersal of individuals, inbreeding may be more adaptive than out-breeding. The recent introduction of DNA analysis to the field of avian ecology has facilitated research into degrees of inbreeding. It is now possible to strictly assess the relationship between inbreeding and fitness. A decrease in heterozygosity has actually corresponded with the deleterious effects of inbreeding in wild avian populations. For such studies it is essential that we obtain demographic parameters, genetic data, and the parameters of life history traits.To that end it is necessary to introduce populations, or to locate populations of which the year of foundation is known.

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The recent development of molecular methods for sex identification makes large-scale studies of sex allocation in birds possible. This review identifies three types of sex allocation studies of birds. These relate either to the population primary sex ratio, the facultative manipulation of the sex ratio, or to sex-skewed provisioning. Many recent studies have suggested that facultative sex ratio manipulation may be more widespread among birds than has previously been considered. In contrast, only a few studies have been made of the population primary sex ratio, and of sexskewed provisioning. Despite all these studies, the mechanism for adjusting the sex ratio remains a mystery. In particular, estimating the cost of making sex ratio adjustments is indispensable for quantitative predictions of sex allocation. The relationships between the three aspects outlined above have not yet been sufficiently clarified. In both Budgerigars Melopsittacus undulatus and Great Reed Warblers Acrocephalus arundinaceus, fathers provide extra-feeding for a certain sex of offspring, while mothers manipulate the primary sex ratio. I suggest that the distinction between the sexes in terms of providing extra-feeding or manipulating the sex ratio, may in fact affect the population primary sex ratio and cause a bias towards the sex for which fathers provide extra-feeding.

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Human activities resulting from habitat loss and fragmentation have seriously threatened many birds and other fauna to the point of extinction. Almost 20% of bird species were categorized as either endangered or 'nearly threatened' species in 1996 IUCN Red data list.Recent advances in molecular techniques provide us with many tools appropriate to conservation in addition to the field of population biology.Allozyme analysis, DNA sequencing, minisatellite, microsatellite, and random amplified polymorphic DNA (RAPD) procedures enable us to identify parentage, pedigree, founder and bottleneck effects, population structure, effective population size, phylogenetic relationships among populations, as wll as gene flow within and between populations. Polymerase chain reaction (PCR) amplification of small amounts of DNA (nanogram), enable us to analyse genetic profiles without harming endangered birds. They also provide us with sophiscated techniques for analysis of metapopulation structure, hybridization, phylogenetic relationship within and between populations. All information regarding genetic population structure is important for the conservation of endagered bird species. In this review, I highlight the role of molecular techniques for studying bird population structures and for the effective planning of bird conservation strategies. Detailed knowledge of the relationship between genetic variation, environmental factors and fitness are all necessary if bird populations are to be successfully conserved.

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