The introduction section of the peer reviewed research article entitled Mammals In Which Females Are Larger Than Males, by Katherine Ralls, provides valuable information about the research that was, and is to be, the subject of her studies. Readers are introduced to a phenomenon in which female individuals in a species are predominately larger than their male counterparts. Ralls states that this phenomenon has been encountered, and studied, in animals such as birds, reptiles, invertebrates, and amphibians. The author then continues to state that the purpose of her research is to generate a list of mammalian cases in which this phenomenon has occurred. She also then tells readers that she intends to explore the biological reasons as to why a larger female might be advantageous, or problematic, in particular cases of mammals. It is these biological explanations that may pose some controversy in her research.
Why is it that birds, reptiles, invertebrates and amphibians sometimes have species in which the female is larger than the male? In her introduction to her research paper, Ralls explains that Darwin’s theory of sexual selection may play a role in this phenomenon. Other proposed explanations such as dominance over males, inter sexual competition within a species, and a theory known as “Big Mother is Better Mother”, all may play a role in dictating the size of females and males in a species. Throughout her paper, Ralls plans on describing how her research tested and observed each of these theories’ contribution to female mammals being larger than their male partners. However with each of these theories comes some controversy. All of these theories have been demonstrated in the other taxa of animals, but never mammals. Ralls, explains that her research is the first of its kind in mammals, therefore her research is an extension of the work that others have done before her, but cannot be compared to any other research in the mammalian field. The purpose of this paper is to answer just the basic questions that arise when considering this phenomenon of female mammals being larger than males.
Although there is no definite hypothesis being tested in this research paper, questions are being answered with the goal of collecting new data for future studies. We learn in the introduction that Ralls’ goal is to catalog cases of female mammals being larger than males, and then explore the various selective pressures responsible for the females larger size. This work is an extension of previous work because Ralls can look at the theories and questions being asked in other taxa (e.g. reptiles) and apply those to mammals. She can use the methods and procedures of others to generate a research plan for this, and future research. Ralls can observe the problems and failures of this research in other taxa, and change them to make her research more successful than those before her. So, although this research is ‘one of a kind’, there is still a lot of be learn from the way others conducted research in the past.
Although short in length, the introduction section to Katherine Ralls research paper explains to the reader exactly what this study is about and why its information is so valuable. This section of the paper introduces readers to the basic structure of the paper. The introduction also outlines past research, the basic problems, and possible explanations in regards to the phenomenon of mammals in which females are larger than males.
Throughout the rest of her research paper, Ralls describes, in great detail, the procedures she uses to generate the categories of mammals she studied. She then describes how data, such as size of the female, is recorded and interpreted. Finally, she captures and organizes the data into tables, which are listed by category of mammal. Using these tables, Ralls can confidently theorize about each possible biological explanation (which were mentioned in the introduction section) posed for this phenomenon in tandem with the particular mammal she was focused on at the time. Through tedious note taking and analysis, Ralls was able to make some bold statements about how and why nature chooses female mammals to be larger than their male counterparts. These statements do not provide certain proof of this biological phenomenon, but open the door to future research in this new territory study.
References: Katherine Ralls, Mammals in Which Females are Larger than Male