This diploma thesis deals with gender markers of nouns denoting animals in contemporary English. The differences will be researched in technical texts published in both the online and print versions of scientific magazines. The work is divided into two main parts. The theoretical part will describe predominantly grammatical categories of nouns (number, countability, determination, gender, case) connected with gender issues. The first half of the practical part concentrates primarily on observation of animal names, collectives, or their forms in singular and plural. The second half is engaged exclusively in singular pronouns as they able to distinguish masculine, feminine and neutral gender in animals.