**2. Biodiversity**

**1. Global problems**

4 Pure and Applied Biogeography

Overpopulation is in the center of the global problems of humanity. Overpopulation is the primary cause of many other global problems, which are also influenced by some other minor

• Overpopulation is the cause of an increase in the ecological footprint of humanity. This is manifested in the destruction of natural ecosystems, depletion of natural resources, pollution of air, water, and soil [21], an increase in anthropogenic climate change, global biodi-

• Overpopulation increases density and decreases personal space and per capita resources. The human-ethological consequence of these is the growing aggression that is manifested

• Overpopulation and urbanization increase the severity of global health problems and in-

• Decreasing natural ecosystems (tropical rain forests, moderate forests, bogs, marshes, sea-

• Growing populations are mining and burning more and more fossil fuels, which increases

• Global climate change increases demand for adaptability, living costs, poverty, and social

• Global climate change creates conditions for outbreaks of new epidemics (through area

• Reducing biodiversity reduces the biosphere's adaptability (through decreasing functional

• The deterioration of people's living conditions increases the number of people in extreme

These problems are further aggravated by the growing social differences between people, the problems of low schooling of people in poverty, and the lack of political unity of mankind

To address problems, overcome the overcrowding, reduce the per capita ecological footprint, tighten coordination of human activity, reduce social disparities, strengthen social solidarity, environmental protection, nature conservation, and climate protection, improve the education level of humankind, and improve public health, resources may be concentrated on vital

• Global climate change further undermines the living conditions of natural ecosystems.

There are a lot of synergistic interactions between these phenomena, for example:

side habitats, and coral reefs) reduces the biosphere's climate control capacity.

factors. These global crisis phenomena are closely related.

in crimes, terrorism, revolutions, wars, and so on.

greenhouse gas emissions and the rate of global warming.

change of parasitic, vectorial, and pathogenic organisms).

poverty, which further aggravates overpopulation.

crease the risk of pandemics.

aggression and enhances migration.

redundancy).

(195 nonaligned nation states).

versity loss, land-use restructuring [22], and urbanization problems.

In the maintenance and conservation of our planet's biodiversity, knowledge of current biogeographical patterns [23], Earth-historical changes [24, 25], and speciation processes [26] have outstanding importance. Many areas of biodiversity are still completely undiscovered nowadays [27].

The ecological effects of global climate change also have a significant impact on biodiversity, flora and fauna, through biogeographical patterns [28–31].

In the field of nature conservation, a fundamental change of paradigm became necessary due to climate change. The previously dominant "in situ conservation," which is to preserve existing ecological conditions in present habitats, is not always a realistic goal. Consideration should be given to active "eco-engineering" interventions that support the spatial shifts of natural communities as adaptation options. In this, the biogeographic knowledge and the identification of climate-analogous areas could have great importance. It is obvious that such studies should combine analyses of current and Earth-historical biogeographic patterns with climatic scenario-based predictions.

In the biogeographical research on biodiversity, the following key issues can be identified:

