By Deniz Saygi
The origin of modern humans has always been an intriguing yet mysterious subject. Mythological elements, depending on the traditions presented by each society from the past to the present, have shown and continue to offer many different cultural elements, belief styles, rituals, and social beginning and still offer much to explore. (Saygı, 2021).  To ensure the continuity of their lives and societies, all living things must adapt to their habitats and are subjected to an evolutionary process. (Lorimer, 1993).  The process of adaptation to nature transfers the hereditary characteristics of the future generations of organisms depending on their growth, nutrition and other environmental factors. (Gardner, 2017). 
Ancestors of modern humans is spread throughout the world by generally making one-way migrations within both large and small populations (Lorrimer, 1993).  Scientific developments, geneticists can now trace ancestry back in time by analysing the DNA in living human populations and give a chance to study the histories of migrations of people’s families. (Lewin, 2005).  Although DNA studies have revolutionised the field of palaeoanthropology, this story is not as simple as people think, mainly because if the inferred mutation rates are not correct, the migration timeline can deviate by thousands of years. (Lewin, 1998).  Modern humans settled in Indonesia, Papua New Guinea, and Australia through migrations 45,000 years ago (Leavesley et al., 2002).  The moderns travelled to Europe about 40,000 years ago, probably by two routes: via Turkey to Eastern Europe along the Danube corridor and to the Levant along the Mediterranean coast. So, the ancestors of modern humans were firmly entrenched in much of the Old World 35,000 years ago. This migration of moderns led to the extinction of Neanderthals, who were forced to live in the mountains in Croatia, the Iberian Peninsula, Crimea and elsewhere, 25,000 years ago (Hublin, 2017). 
According to Merriam-Webster , ‘’migration’’ is defined as the act, process, or instance of migrating, which means to move from one country, place, or locality to another.  Considering today's dynamics, the concept of "migration" has become a more profound and global dynamic.
Migration movements can be divided into two categories as; internal and external migrations.  Internal migration is the displacement that takes place within the country's territory. Internal migration may occur because of rapid population growth in rural area leading to less work opportunities and financial difficulties, increasing job opportunities and a certain lifestyle expectation in urban areas, better social and health opportunities in urban areas such as kinds of universities among many other reasons. 
External migration (long distance among continents or outside the country) can happen because of various reasons including relocating in case of war. Inadequate financial situations due to economic losses, natural disasters, religious, political, sociological, and cultural reasons. 
Migration can also be defined as a set of processes that start with a change in perception, continue with displacement in space, and are complete with adaptation to the destination. In this sense, the "actor" of migration is the "human" who acts under change, experiences the processes from the beginning to the end, and faces the consequences for years. Gordon Marshall defines the phenomenon of migration sociologically as the permanent movement of more or fewer individuals or groups beyond symbolic or political borders towards new settlements and societies. 
Anthropologically, migration is interpreted as a cultural phenomenon and a set of processes beyond the dimensions of spatial displacement and demographic structural/institutional change that sociology deals with. According to the "diffusion" theory of 20th-century anthropologists, discoveries, inventions, and cultural developments in various societies are not independent or parallel to each other. Hence, discoveries, innovations, and cultural developments took place once in a particular region, at one specific time in history, and in a specific society, and spread from there to neighbouring societies and the world. 
Although the forms of migration have undergone some changes, they have some common tendencies in general terms. The first of these trends is the globalisation of migration. More and more countries are simultaneously affected by migration movements as migration gains a global character and the geographical diversity increases. Most countries receiving migration accept migrants from various economic, social, and cultural backgrounds. Another trend is the acceleration of migration. Today, especially international migration movements are growing in volume worldwide. This situation increases the importance of government policies with regards to migration and impacts the state infrastructure. The third trend is the differentiation of migration. For many countries, migration includes not only a type of labour migration, refugee or permanent settler but also a meaning that encompasses all of these. The last trend is the feminisation of migration. Women play a role as an important figure in all migration zones and most forms of migration. 
Since migration is a collective action caused by social change, it dramatically affects society and social structure in receiving and sending countries as an ethnically differentiated society through immigration forms, the policies required by the labour market (with far-reaching consequences for social relations, public policies, national identity, and international relations) often result in the marginalisation of ethnic minorities.  Migration is not simply a movement of displacement. While immigrants leave their accustomed lives, they do not only carry their bodies to the place where they migrated. At the same time, it takes its cultural formations, experiences, briefly all behaviour patterns to new areas and creates a space of cultural interaction and clash. This dynamic character of migration also makes it difficult to determine the effects of migration on the social sphere. Individual perceptions, attitudes, values, and the situation or difference in political, social, economic, and cultural phenomena are the main factors that determine the reflections of migration on social life. On the other hand, the typology of migration is another critical factor. 
It is necessary to analyse the reflections of migration on social life through migration results. Instead of evaluating individual migration types, it is aimed to evaluate the results of the migration phenomenon in general terms, based on some basic criteria. At this point, one of the most important results of the migration phenomenon is integration. Integration means harmony. Integration is one of the most important results and problems of migration, whether it is internal or external migration, voluntary or forced migration. Every place has its own set of rules and lives. As a result, both the immigrants and the life in the context of the place of migration require mutual interaction. This process brings with it some problems, as the unique social structures of the immigrants will interact with the unique system of the migrated place. 
Another factor in the context of the reflection of migration on social life is the economic cost caused by migration. Regarding the context of the country of immigration or the place of immigration, this situation ultimately brings a financial cost to the agenda. While migration is a process that directly affects the labour market, it also means new unemployed and new resettlement policies. Furthermore, when considered in the context of internal migration, the imbalance in the distribution of the population across the country will cause uneven distribution of investments. In addition, uncontrolled population growth will cause inadequacies in services such as infrastructure, health and education in cities and decrease the quality of these services, which will mean new economic costs. In short, financial problems such as employment and labour force, city management, spatial changes, and income distribution will arise in the cities that receive immigration. 
Every migration also brings its own story. There are many dimensions such as experiences during migration, difficulties faced by immigrants in the face of displacement, the difficulty of adapting, getting used to a new language, a new place and new people, and living with a new culture. Moreover, migration is a process that closely and deeply affects social life in the context of integration and social change and contains many personal feelings and thoughts such as hopes, dreams and aspirations.
Conclusively, the migration phenomenon, which is the process of "relocation" or "horizontal mobility" of people, groups in time and space, either compulsory or voluntary, can be based on socio-political, socio-economic, socio-psychological, and cultural reasons. When considered in the context of both the immigrants and the place of migration, migration is a process that deeply affects both sides. In order to understand this process, the reasons for the migration of the immigrants, the migration process, the characteristics of the place of migration and the new situation encountered in the place of migration should also be analysed.
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Deniz Saygi is a current PhD student at Middle East Technical University in Science and Technology Policy Studies. Deniz also holds degrees from Ankara University (MA Latin American Studies) and TOBB University of Economics and Technology (BA International Relations and Affairs). Deniz writes contributions for the Earth Refuge, Human Rights Pulse and Sustainability for Students. She currently is selected as the Max Thabiso Edkins Climate Ambassador for the Global Climate Youth Network hosted by the World Bank.