1. Genetics
The diagram above is a representation of the genetic system. DNA stores and transmits information. Genes, comprised of DNA, contain the coded information to make proteins. The proteins are the do-ers, can also be regulators or switches, they can control sets of genes that encode more proteins. As regulators they switch on or switch off specific attributes of the organism, such as colour, structure, material, texture*. Proteins are context specific, for example are expresses only in dark, or only in light, only in head, only in limb... Proteins also 'make' pigment as enzymes.
2. Adaptation
A definition of Life: DNA based, it can adapt, it can replicate itself.
DNA can change by mutation thus providing variation that can be selected for in response to changing environmental conditions.
A designer could harness 'adaptation' from biology.
Evolution is 'bricolage', evolution uses the materials available at hand to create. Evolution does not design to the optimal most efficient solution, it will evolve until it works, then will remain that way until environment radically changes.
3. The Vascular System
The vascular system is formed through 'canalisation'. It is not predetermined, but occurs as water flowing down a bank of soft sand will form pathways, the vascular system forms through cells in a plant. The vascular system, once the 'water' starts flowing down the 'bank', will self-organise into a pattern. Canalisation is conveniently also the term for the production of canals.
The cells die along the path of canalisation to form rigid tubes for water movement.
Thus the pipework has a fixed diameter, to increase flow the number of pipes is increased. Below is a film still of the Islington tunnel along the Regents Canal, reminiscent of a vascular tube...
4. Methodology
Miltos and Angela broke down their research interests for me like so: Miltos's research is how different species have different morphologies, specifically relating to leaf shape, and Angela's research is on mechanisms through which form evolved.
They developed together a framework, or system, for research which is based on genetics, as they required a different system to what already existed to allow them to ask different questions.
Angela described two methodologies she uses: 'Induced Variation' and 'Natural Variation'.
For the question: 'why a particular flower species has fewer petals?', using the first method of 'Induced Variation'
1. she introduces random mutations in the genome, creating an 'artificial evolution'
2. these plants are grown
3. she looks for mutant plants which have gained petals, ie. they have lost the function of the gene to have fewer petals. Therefore the gene lost is the gene required for petal loss.
4. the gene identified leads to identifying the protein expressed by the gene
5. she can work out what this protein does.
Using the second method of 'Natural Variation', Angela would collect plants of this species from all over the world, and look for variations in petal number. She is then able to map the genes responsible for the variation. By sequencing the DNA of these genes she can see what sequence variation evolved by natural selection.
Angela described a method to investigate structural components of cell walls, filming in high speed a seed pod's explosive release. The pod releases its seed in less then 3 milliseconds, an action one cannot see unless it is revealed through high speed film. The film takes 10-15,000 frames per second. The mechanism of the explosion and the residual stresses that build up in the pod to eventually cause explosion can be modelled and related back to the structural properties of cell walls in the pod.
*proteins also 'make' pigment as enzymes.
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