Biology is not a factor that contributes to cross-linguistic patterns in language variation. Geography, culture, and history are all factors that can influence the way that languages vary across the world.

Language change is the term for the process by which languages change over time. Language shift, language drift, and language evolution are all related concepts, but they refer to specific aspects of language change.

The use of SOV word order in many languages is an example of a cross-linguistic pattern in language variation. The use of the definite article in English, the use of the subjunctive mood in Spanish, and the use of the ergative case in Basque are all examples of language-specific features.

The Sapir-Whorf hypothesis is the term for the relationship between language and culture. It proposes that the structure of a language can influence the way that its speakers perceive and conceptualize the world.

All of the above geographical factors can contribute to language variation. Mountains, rivers, deserts, and oceans can all act as barriers to communication, which can lead to the development of different languages or dialects.

Language shift is the term for the process by which a language is replaced by another language. Language change, language drift, and language evolution are all related concepts, but they refer to specific aspects of language change.

All of the above historical factors can contribute to language variation. The migration of a people, the conquest of a people, the colonization of a region, and the spread of a religion can all lead to the development of new languages or dialects.

Language convergence is the term for the process by which languages gradually become more similar to each other. Language divergence, language assimilation, and language leveling are all related concepts, but they refer to specific aspects of language change.

All of the above social factors can contribute to language variation. The social class of a speaker, the gender of a speaker, the age of a speaker, and the occupation of a speaker can all influence the way that they speak.

Language divergence is the term for the process by which languages gradually become more different from each other. Language convergence, language assimilation, and language leveling are all related concepts, but they refer to specific aspects of language change.

All of the above linguistic factors can contribute to language variation. The sound system of a language, the grammar of a language, the vocabulary of a language, and the discourse patterns of a language can all vary across different languages.

Language assimilation is the term for the process by which a language is assimilated into another language. Language convergence, language divergence, and language leveling are all related concepts, but they refer to specific aspects of language change.

All of the above psychological factors can contribute to language variation. The attitudes of speakers towards their language, the beliefs of speakers about their language, the values of speakers about their language, and the motivations of speakers for using their language can all influence the way that they speak.

Language leveling is the term for the process by which languages gradually become more uniform. Language convergence, language divergence, and language assimilation are all related concepts, but they refer to specific aspects of language change.

All of the above pragmatic factors can contribute to language variation. The context in which a language is used, the purpose of a conversation, the relationship between the speakers, and the social setting of a conversation can all influence the way that speakers use language.