Quantum Forest

Today’s Radio National Morning Show, hosted by Tim Cox, introduced yet another absurd story: forest companies are planting genetically modified (GM) trees that are unpalatable by wildlife and, ergo, animals will starve. Lets go by parts:

• There is no planting of GM trees in Australia.
• Forest companies do perform traditional breeding.
• There have been studies, by the CRC for Sustainable Production Forestry, on the potential of increasing unpalatability of trees to avoid mammal browsing.
• The shift of unpalatability could act as a minor deterrent for browsing animals, but would not avoid trees being eaten.

Some further explanations and detail about breeding. Say that we are interested in improving the quality of tomatoes, where quality is measured with a ‘taste score’. We could look in our backyard for the plants with the highest taste scores and cross them, in the hope of obtaining progeny with tomatoes that are tastier than those coming from the parent plants. The response to selection will be directly proportional to three factors: the degree of genetic control of taste (called heritability, h²), the observed variation for the trait (called phenotypic variance) and the intensity of selection (for example, are we selecting 1 every 10 plants or one every 10,000 plants?). The same approach is applied using more sophisticated statistical techniques when breeding cows, corn, trees, etc. This process changes allele frequencies, so alternative forms of genes that are more favourable—that is, they improve taste—are more frequent in the population of tomatoes in our backyard.

Coming back to palatability of trees, its degree of variability and genetic control will allow only a small shift of its average. This will be a contribution towards a reduction of 1080 use through making seedlings less tasty, but it will not stop animals eating the plants. Thus, it will be just another tool for an integrated approach to mammal browsing management.

We could go even further with traditional breeding, and obtain hybrids crossing two varieties of tomatoes or trees, to combine desirable characteristics and/or look for hybrid vigour (heterosis). This would still be in the realm of crosses possible to obtain without human intervention.

A different, more high-tech approach, is the so called ‘genetic modification’ or ‘genetic engineering’. This consists on isolating a single gene from an individual, and introducing it in the genome of another individual. In this case, we are not subject to reproductive barriers, and it would be possible to put a gene of, say, a fish into the genome of a plant. Thus, through this process we can create organisms that could not exist in nature without human intervention. This is not being used in Australia; forest companies already have enough problems without the need for introducing yet another point for discussion.

Incidentally, I have no problem with genetic modification, but many neo-Luddites can not tolerate the idea. Anyway, the whole ‘GM antipossum trees’ story could fit well with other conspiracies like Jewish attempts of world domination, the use of nano-nuclear bombs in North Korea, and the abduction of Princess Di and Elvis by aliens.