What are some methods you could use to measure the amount of white in every juncos tail feathers imagine you had the equipment people and funding you needed to accomplish this

Evolution is the process that allows the appearance and elaboration of signals, but the key question is: what selective forces led - and lead - to the appearance of color characteristics and chromatic patterns ?, not only in the scope of a species concrete - such as the black bib of the common sparrow (Passer domesticus) - but also within each family or even within a wider framework, for example the light colored spots that we see in the outer feathers of the tail of the bird species Dr. Senar explains the methods and results of the experiments performed so that the reader can compare their interpretation with the scientific advocacy, but also involve other alternative hypotheses. For example, the supposed signals of dominance Do they represent correlations with age and sex, which in turn correlate with dominance? And what can we say about deception, of those signs that exaggerate the status of an individual? The presentation of the different alternatives offers the reader the opportunity to detect the complexity of the selective forces and the difficulty of designing clear and conclusive experiments. In a similar way, the author presents the multiple hypotheses that address sexual selection and delayed maturation of plumage, thus facilitating the reader, understanding of the different topics discussed and a better appreciation of the elegant experiments that have been used to formulate and defend some of these hypotheses. Camouflage is treated in a separate chapter, but Dr. Senar not only focuses on the colors of the prey, which affects the object of investigations, but also on the color of predators, whose study has been the subject of much attention minor The interpretation of color as a bioindicator is an innovative approach that is proposed towards the end of the book. This is the first time that this possibility was raised, but, as the author points out, if the birds determine the quality of the habitat by the color of the potential couple that lives in it, there is no doubt that we should also be able to determine the quality of a habitat using similar means. Experiments that allow us to evaluate this approach are described throughout the book.

parasites can detrimentally affect their host, but also must not allow their host to die before they can complete their life cycle. some parasites have complex life cycles with many different hosts, and have had to find ways of persisting in many different environments during the change from one host to another. ectoparasites live outside the body of the host, and can more easily  disperse, but are  more exposed to predators, parasites, parasitoids. endoparasites live inside the body of the host, and are therefore protected from the outside environment. but they can be  attacked by the host's immune system. they have therefore developed  mechanisms for dispersal such as  complex life cycles.

hormones in blood stream

image: dtc.ucsf.edu

endocrine glands secrete hormones into the blood stream near them; the hormones then travel in our bloodstream until it reaches its destination, called a target cell, in distance parts of the body. in the target tissue, hormones lock onto the target’s plasma membrane, called the receptor site.