Ans.

Biogeography is an important branch of Physical geography which deals with the distribution of various species and ecosystems geographical and throughout geological time and space. The term ‘Biogeography’ comes from two words i.e.- bilogy and geography. Here biology indicates the biotic things, which referee, to the plants and animals and geography refers to the study of the earth surface with respect to biotic and abiotic components. 

Biogeography is the study of the distribution of life forms, past and present, and the causes of such distributions. It includes the application of biochemical techniques for genetic analysis and application the large-scale analysis, incorporating remote sensing, of biogeographical patterns; studying and modelling ecosystem dynamics and metapopulation dynamics; poblems of speciation and genotypic variation; and the analysis and daing of the palaeo-biogeographical record. Bio geographers may also be concerned with environment-related food and health issues. 

Accordingly, the study through biogeography is the study about biodiversity. Nature of the lives of flora and fauna where biologists are paying attention regarding their physical shapes and characteristics, a theoretical and conceptual ideas provide a detail study under the biogeography field. Therefore, biodiversity carries a very important place in the scope of biogeography. The reason for this is that Biogeography enables us to study different characteristics and features in different regional environments with a geographical view point. Accordingly, it enables us to identify the environmental diversities of Biogeography and the fluctuations of diversities and the problems arising in the environment.

Biogeography may be defined simply as the study of the geographical distribution of organisms, but this simple definition hides the great complexity of the subject. Biogeography is often study in the context of ecological and historical factors, which have shaped the geographical distribution of organisms over time. Specifically, species vary geographically based on latitude, habitat, segregation (e.g., islands), and elevation. The sub disciplines of biogeography include zoogeography and phytogeography, which involve the distribution of animals and plants, respectively.

Richard Hagette have also mentioned significance of these questions in his own words. Bio-geographers address a misleadingly simple question: why do organisms live where they do? Why does the speckled rangeland grasshopper live only in shortgrass prairie and forest or brushland clearings containing small patches of bare ground? Why33

does the ring ouzel live in Norway, Sweden, the British Isles, and mountainous parts of central Europe, Turkey, and southwest Asia, but not in the intervening regions? Why do tapirs live only in South America and Southeast Asia? Why do the nestor parrots – the kea and the kaka – live only in New Zealand?

Meadows and Pitman describe about biogeography as follows. ‘Biogeography is an interdisciplinary natural science with a complex, even cryptic identity that defies definition. In essence, it is the science of the distribution of living organism and the factors that underlie this distribution. Such a one-line descriptor does no justice, however, to the range of approaches and concepts that constitute contemporary biogeography. Not only is biogeography concerned with spatial patterns in the contemporary sense, but also there is a strong evolutionary component and a concern with change over time. It is a discipline that leans heavily on several other scientific fields of enquiry, such as ecology, systematics, the environmental sciences, the various branches of physical geography and even, in an applies context, aspects of the social sciences’

According to that definitions biogeography is concerned with the biological phenomena in space, especially in terms of the distribution of various kinds of floral and faunal species. It has developed interact with many other subjects and try to seeks relationships between living beings and non-living things with change over time.

There are two branches of biogeography i.e. - (i) phytogeography or geography of plants which deal with the study of the distribution and classification of plant species and (ii) zoogeography or the geography of animals which deal with the study of the distribution of animals in respect of the geo-environment.

Scope of Biogeography:

The scope of biogeography is not clearly demarcated. Biogeography enables us to identify biodiversity patterns in the past and present, identify the expansion of organisms while enables us to study about the relationship between living and non-living factors influence organisms to exist. Diversity of flora and fauna exists according to the relationship that emerges with the above factors. It studies the distribution of biological materials over the earth’s surface and the factors responsible for the observed spatial variations

Biogeography is the study of the geographic distribution of plant and animal species and ecosystems over space and time. Its scope is the entire biosphere from the beginning of life.

Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, isolation and habitat area. Biogeography as a science is the synthesis of concepts and information from geology, physical geography, evolutionary biology, and ecology.

As our climate changes and the sixth great extinction transpires, vital biogeographic research reveals changing dispersal patterns of species and any physiological and ecological constraints on their movement. Biogeography also provides better understanding of evolutionary time frames and global spatial scales involved in climate changes throughout geologic time.

Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, isolation and habitat area. Biogeography as a science is the synthesis of concepts and information from geology, physical geography, evolutionary biology, and ecology.

Biogeography seeks to describe and analyses distributional patterns exhibited by organisms at present and in the past. To enable it to comprehend distributional patterns, biogeography needs to study physical and organic factors as they are now and as they have been in former time. To acquire this knowledge, it must use information drawn largely from the natural and earth sciences. It is an interdisciplinary subject within these domains.

There are two branches of biogeography i.e. - (i) phytogeography or geography of plants which deal with the study of the distribution and classification of plant species and (ii) zoogeography or the geography of animals which deal with the study of the distribution of animals in respect of the geo-environment.

Modern biogeography explores spatial patterns in the geographic variation of individuals and populations, including genetic, physiological, and morphological variations. Organisms are often studied in biomes, consisting of distinct flora and fauna related to climate, soil, and geological factors.

Changes in flora and fauna life take place according to the climate. As for animals, animals living in warm regions are different from animals living in cold regions. Studies are carried out by biogeography in respect of lithosphere, living beings of interior earth, there living begins, soil and rocks. It studies more on soil than rocks and pays attention about carnivorous fauna as stagnated in caves without sunlight and food production (eg: Cactus plant) and also about mass movement of micro ecological systems. Rocks also cannot be set apart from biogeography. As an example, coral reefs form after having being water borne for a long period. These are particles of organisms which have be under water. When such corals decay they form a different type of soil region. In those soil regions changes could be observed according to various climatic conditions. This type of soil causes a diversity in the evergreen trees growing in this area. Attention is paid towards human effects in addition to physical and biological factors. Especially, the natural flora changes in agricultural process. Accordingly, biogeography studies about the human effects towards the environment.

The subject of Biogeography includes certain fundamental problems and this subject can find solutions for such problems. These problems are:

a) Why various types of organisms are could be seen on this Earth?

b) Where have these organisms spread?

c) What is the reason for the spreading at such places?

d) Can that diffusion pattern maintained continuously?

e) Do various changes take place in maintaining it continuously?

f) What are causations for different change?

g) Similarly, how will the diffusion patterns change in the future?

h) What are the factors that influence such changes?