There is a grandeur in this view of life.”


Darwin & Mendel: the two sides of a biological “coin” – behavior & inheritance.


1,      Darwin and Mendel's legacy–“lessons about limits in another person's eyes”      F

2,      The Entangled Bank        more lessons of natural laws from all around us         M

3,      Our Distant Past      “rocks of ages” unseen remnants of a forgone world           F


outline | Limits | Evolution | Terms | Main Points | SUMMARY




            Unknown to one another Darwin and Mendel discovered that variability and selection work            

            in tandem to produce viable offspring—members of a potentially breeding population.


            A biological “coin” ? –

                        one side is behavior–ethos &

                        the other side is inheritance–genetics.



            Eight significant points are the heart of the chapter, foreshadowing the book: within limits, “descent with modification” from a common ancestor leads to diversity over time, random mixture generates genetic variability, immunity or resistance, and biotic potential.

Thus, this hereditary composition of a population assures our effective survival, if not breeding.



                        moths, birds, anoles, fruit flies, human blood cells, eye color, and enzymes.


               Conditional (surroundings) change + genetic inheritance = descent with deviations

      it is usually very hard to select for just one characteristic.”

                        a gene consists of a series of nucleotides with different  bases that determine the                 sequence... proteins”  [with alterations = modifications = deviations]


                        proteins (enzymes & hormones) are life’s essential constituents, arbiters, & threads.



            We like all of nature’s species are the products of variation & selection. To know truly what limits we have & how this biological treasure we are endowed with functions, we must unravel a complex puzzle among: the earth, ethology (behavior), ecology (surroundings), & molecular biology (competing means of regulatory feedback).


Our task is to better know the world in us!




                                    Why do your eye colors differ only within a limited range?


Three laws of thermodynamics

            1          energy (and matter) can neither be created nor destroyed; energy (E) is constant (k)             

            2          no transfer of energy is ever completely efficient and heat, as a loss, accumulates

            3          eventually the universe will have insufficient energy for life


Said another way, by Garret Hardin

            You can’t win

            You are bound to lose

            You cannot get out of the game




descendants vary with respect to the traits they inherit and thus what survives depends on what was produced earlier [1] by variable parents and grandparents.

                                    Nothing really evolves, but descendants vary greatly from their ancestors

                                    Some of that variable inheritance is passed on

                                    Not all traits are passed on, but natural selection favors functional assets

                        So in a population many traits survive that can endow future offspring with variety

                                    Variety is insurance against the storm

                                    There are no guarantees of success

                                    Life has the capacity to adapt to conditions that are not too extreme

                        Over time due to isolation and variation, populations give rise to new species:

                                    Finches on the Galapagos Islands



Eight significant points:

1.    Populations change within limits [milieu’s limits + genome’s limits]

2.    Natural selection favors some traits among very variable offspring’s genomes

3.    Isolation (loss) and the pace of change among organisms can be rapid or slow

4.    Linking evolution to genetics is the Modern synthesis and a foundation of biology

5.    Artificial selection by humans and other organisms can change other creatures (fruit flies, cows, cats & dogs, sheep, GMOs]

6.    Change in the hereditary composition of populations over time is due to DNA and RNA’s variability and functionally replicable chemistry.

7.    Genotype & phenotype act in such a way as phenotype is selected for as an expression of genotype [eye color in humans].

8.    Changes in a population’s genome is the raw material of evolution or shifts–alterations–in populations of organisms over time.


We are the products of the world we see around us, limited by its conditions plus our inherited and acquired traits to wither or prosper; as we can become proper caretakers, or unreasonable exploiters of an unimaginably expensive endowment, which I will call life’s diversity, beauty, and integrity on an imperiled planet.


  1. Laws enabling limits and optimization
  2. Descent from a common ancestor
  3. Inherited resistance

outline | Limits | Evolution | Terms | Main Points | SUMMARY

The Dominant Animal on the web

Dominant Animal

Storm Over the Amazon


[1] Contingent subject to chance or happening only if, or anticipated to arise if a particular event occurs