{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

lec_1_cond_13

We will describe the phenotypes in terms of a

Info iconThis preview shows pages 3–5. Sign up to view the full content.

View Full Document Right Arrow Icon
We will describe the phenotypes in terms of a RESOURCE BUDGET G F P G This phenotype invest mainly in fecundity This phenotype has equal Investment in all 3 functions -reflects tradeoffs of energy, minerals, etc. put into Growth, Protection, and Fecundity Consider a hypothetical plant: To keep our analysis simple we will make three simplifying assumptions: 1) Annual life cycle 2) Asexual reproduction 3) Entire phenotype coded by a single gene To proceed further we are going to carry out a simple thought experiment. WHY - this allows us to strip away all unnecessary complexity and focus on the process of evolution rather than the details. If more resources are put into one function, then there is less left over for the other functions
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Some evolutionary geneticists consider phenotypes like you and me to be "throw-away survival machines" used by genes to transport themselves from one generation to the next. - Do sexual organisms reproduce themselves? Look in a mirror. Have your parents reproduced themselves? - Do genes reproduce themselves? Yes 99.999% of the time Genes potentially live forever by jumping through time within organisms (throw-way gene transport machines) (Genes) Phenotypes Gametes (Organisms) Zygotes 8) Why can we conclude that organisms are designed to be good gene transport machines? Because those genotypes that code for phenotypes that transport more gene copies from generation to generation will eventually predominate within a population. Changes in the relative frequencies of Process of different genotypes (genes) due to differences Natural Selection: in the associated survival and fecundity of their phenotypes. 4a 5) Suppose a new herbivore was introduced into the meadow so that the level of damage produced by herbivory was raised, but only slightly. Which phenotype has highest fitness now? 6) Does any one attribute (G,P,F) determine fitness? No, it is the combination relative to the demands of the environment. E - Note: This example indicates that fitness is not an intrinsic characteristic of an organism, but rather a measure of the match between the characteristics of an organism and the prevailing demands of the environment.
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}