International Aroid Society

This was written to me by Kirsten Llamas, author of Tropical Flowering Plants, and she has given me permission to post it.

John.

“Subject: RE: [Aroid-l] Holes

The answer to the problem, if there IS one, is worthy of courses in physiology and anatomy. No one should think that science challenges their belief system. One only needs to have a little flexibility when interpreting the time references in the bible. “a “day” can have multiple interpretations. We often hear the expression “in my day”, to mean the entire period of our youth. Days before there “was light” is not something we can interpret since night and day is 24 hours to us and there are as many days in a year as it takes for Earth to circle the sun. Without the sun’s light what was a day worth?

It is important to use the right terms. NO scientist should use the expression that humans evolved from apes (there were racist connotations associated with apes and monkeys at the time). The correct representation is that we share common ancestors that were neither ape nor human as we know them today. The difference is not something we have to argue about. Apes certainly evolved in a different way. However humans share almost the same DNA as apes. Interestingly enough apes are much better adapted to their niches on Earth than humans are. Apes owe their destruction – not to their environment but to human predation. While they thrive given their natural habitat, hundreds of thousands of human babies die every year because we are so poorly adapted that they destroy their own habitat. But we are also cleaver so some of us survive in spite of our poor adaptations.

Most people think that evolution takes hundreds or thousands of years. Wrong. Many studies, including some on bird adaptation of the Galapagos and plants near the HI volcanoes prove that adaptation can take place in a matter of a few generations. This is a separate process from gene changes we call mutations which happen all the time.

Mutations may be caused by natural cosmic rays, chemical or accidental changes in the gene arrangement during cell division. Cell division goes on all the time and it is a marvelous process and a wonder that it does work a large percentage of the time. Often cells do NOT divide properly either during mitosis (leading to such illnesses as cancer) or during meiosis (reduction division into sperm and egg). Most mutations are lethal or weaken a species though not always. Many miscarriages are caused by improper division of the gametes or during fertilization. Some birth defects are the product of improper division of cells during gestation, others are inherited.

DNA changes do not mean that plants or animals flip genera. DNA changes are not even necessary to produce somatic changes. The vast majority of our genes are inactive. For various reasons certain genes are activated while others become quiescent. If environmental conditions are suddenly changed genes may be activated that were quiescent. In a Galapagos study a certain bird living isolated on an Island has a delicate beak that thrives when conditions are wet, but when a dry period arrives, within a generation or two the birds develop beaks that can crack the seed of drought tolerant plants. In another studies in HI, the flow of lava streams separated a large population of different species into smaller gene pools in many separate niches. Within each nich different varieties evolved in a few generations.

Recessive genes may suddenly become the majority rather than the normal minority of 1 in 4. [e.g. if brown-eyed humans who carry recessive blue eye genes are segregated from dominant brown eyed people, within 2 generations there will be blue eyed people running around in the segregated population. There is no particular advantage of brown eyes over blue eyes. But Europeans are much more often blue eyed than Africans and Asians who are usually brown eyed.

In addition the study of biology (forget the word Evolution) shows that plants and animals produce mutations constantly but most are lethal. Look at the numbers of seeds produced in one pod/capsule that do not sprout and those that sprout may be stronger or weaker (or pups with a stronger or weaker sibling). Only those with good survival characteristics are able to reproduce in numbers that can survive living in their niche. (e.g. plants in cultivation would not otherwise survive in the wild that have certain spontaneous mutations/ sports such as too much variegation which lack sufficient chlorophyll. These plants often “revert” spontaneously to the norm).

Mutations are rarely beneficial to a plant or animal. The benefit may be viable in one type climate but not another. If there is no rain for a few years than one variation of a species may survive and another die off. That explains why species with wide distribution – e.g. Tecoma stans ot Tabebuia impetiginosa – may have adapted to wet and dry niches, poor or rich soil. Conversely mutations that are not beneficial will die off. We have that problem all the time trying to cultivate the same plant in our different gardens. Of course we can nurse a plant along in the garden but nature is not going to help poorly adapted species. It kills them off ruthlessly. Nature does not PRODUCE adaptations. Many characteristics are produced and only those that are advantageous survive. An understand of various forms of pollination is helpful to understand plant distribution and adaptations.

Therefore it is not necessary to explain why one species of Monstera has holes in the leaves while another species leaves are deeply lobed. But if you look carefully the holes in Monstera leaves represent the line along which the lobes would form but are discontinued at intervals near the midrib by the lamina. The holes simply represent incomplete division of the blade into lobes. There may be none or several reasons why lobes are a beneficial. Ask yourself why the juvenile leaves do not have the holes. A good reason could be that the lack of light at ground level calls for more chlorophyll producing area. Also leaves in shade tend to become larger (relative to the size of the plant of course). Leaves of the same species may evolve from simple to divided, e.g. Tabebuia spp and then back from 5 divided to 3 (trifoliolate) or one (unifoliolate).

Finally there are fossils that provide evidence of evolution by passive adaptation through many generations. Only higher animals are able to adapt purposefully and individually.

The buildup of microscopic organic compounds that border on life forms is all around us. There are microbes and viruses that are considered to be sub-living but reproduce through infection of living cells. There are probably a great variety of potential life forms in the oceans at certain depth and temperature. Or perhaps all around us. When do organic compounds cross over into living? We often contemplate life on other planets. It will not resemble life as we know it so would we recognize it? Look how long it took us to identify HIV and we knew it had to be there. So what is happening microscopically with the things we do not even know are there.

What is really to the point is the concept of consciousness. At what level of life does it begin. How do we think?

Biological processes converge and reform. We die, our body degenerates into various compounds and atoms that are taken up by other living organisms. We eat and breathe in the molecules of what were once parts of other plants and animals or other humans that came before us and they are at least temporarily part of our bodies. We give them life though we do not give them consciousness. Or if we are what we eat, then what?

We humans can’t answer everything nor has anyone proven anything beyond a reasonable doubt. It REALLY doesn’t matter. These theories are not mutually exclusive. We just have to open our minds to the means by which they connect.”

From: aroid-l-bounces@www.gizmoworks.com [mailto:aroid-l-bounces@www.gizmoworks.com] On Behalf Of Jason Hernandez
Sent: Thursday, March 08, 2012 11:56 AM
To: aroid-l@www.gizmoworks.com
Subject: Re: [Aroid-l] Holes

I will address several respondants at once.

hermine: "ps why is broccoli like that?"

Broccoli is a highly domesticated form of sea kale, as are kale, collard, cabbage, and cauliflower. If you look at a broccoli plant growing, you see the big, collard-like leaves, with the broccoli head coming up in the middle. Let that broccoli head grow without picking it, and it will turn into a flower stalk much like those of various wild mustards. Broccoli is like that because over the years, people selected for a thickened flower stalk with buds packed tightly together and taking longer to open.

Peter Boyce: "On what basis would the primeval leaf be linear?"

I was thinking of such fern allies as Equisetum and Lycopoduim, as well as quillworts, all of which have various combinations of linear structures which function as leaves. It seems to me these would have been derived from the strings of cells in filamentous algae, but I could be wrong about that.

Vincent: "What I mean by created was is in made that way originally by God."

I am familiar with all of this, as I was raised a creationist. I found it left too much unexplained, and had to do a lot of interpretation to make the science fit the foregone conclusion: as you do admit, organisms have the capacity to adapt, and this is the essence of evolution. As to the origin of DNA and its authorship, I never have understood molecular biology, so I refrain from comment.