Metabolic Ecology Flashcards
Are the patterns of intensity of both intraspecific and interspecific competition the same throughout succession
Both grow equally through early stages but interspecific competition which is a max during the later middle stage of succession when rate of species loss is the greatest
Whereas intraspecific competition continues to increase through the late stages of succession
Explain the reciprocal pattern of production and overhead through succession
In early succession the community is dominated by our selected species and therefore production is Max and overhead is min
When the energetic demand of overhead equals energy availability competition ensues, this causes weaker species to be lost in favour of more competitive which increases biomass. In turn overhead increases and production is a min but overhead is at a max
Contrast the principle of least action and principle of the most action
PLA: Where the energy gradient is eliminated as quickly as possible (max rate possible)
PMA: Defining characteristics of life which must maintain the energy gradient (Success at every level is defined by how well the gradient is successfully maintained)
Why is ecosystem development constrained to progress in only one direction
Because as the ecosystem develops it will always progress towards greater energetic throughput as mandated by PLA
This can be accomplished through increasing biomass by PMA and therefore development can only be unidirectional
Define autocatalysis in an ecosystem context
A catalyst is something that accelerates the rate of reaction
Autocatalysis Is therefore a reaction that produces a product that is it self a catalyst of the reaction producing it. In the ecosystem a predator consuming pray will increase growth of primary producers Through fertilizers. More primary production creates more pray which creates more predators and in turn creates more fertilizer
How does autocatalysis affect system resiliency
Long-term autocatalysis decreases system resiliency because it drives the system towards max energy through put
This causes competitively inferior species to be lost to the system in favour of fewer energetically dominant species if left unchecked this will drive the system into collapse
Explain the term the more life, the more effectively the solar energy gradient is reduced
An early successional system is characterized by low density and diversity and therefore modest volume of energy passing through the system. So it’s capacity to reduce the solar gradient this weak
As a system develops through biomass and diversity the volume of energy passing through increases and so does the diversity of relationships. Because energy is lost through energy transfer there is a greater reducing of solar gradient
Moving backward an ecosystem development (complex to simple) Is as impossible as unringing a bell
A bell cannot be unrung because of entropy. This is because high kinetic energy is converted into low grade forms that cannot be transferred or reversed
So when all lifeforms convert high-grade solar energy into biological energy a significant portion is lost and cannot be recaptured. This observation in combination with the PL a and PMA make it impossible for development to progress in reverse
Why is species diversity and abundance in an ecosystem very similar to the abundance and diversity of products in a supermarket
In both cases the diversity of items and the relative abundance of each is determined by selection to maximize throughput (energy or revenue)
How is performance measured
Reproductive output (fitness) is a good proxy measure
Greenhouse example
Nature always works to illuminate energy gradients as quickly as possible (energy leaving through door) in contrast life always works to maintain energy gradients (maintain energy inside)
Wife works to maintain the gradient even though the doors are open this is accomplished by constant input of new energy (photosynthesis in producers and predation in consumers)
How to tell if an exotic species will successfully colonize
Of its presence increases autocatalysis, it’s colonization is guaranteed if not then failure
Individual organisms compared to ecological system
Individuals: seek to max energy gradients between between themselves and the environment. Most successful represented in next population
Ecological systems: grow and develop in such a way as to min energy gradients in the environment
Ecosystem development
Not determinant like a cannon ball
But not utterly unconstrained as well
Processes at work to max energy accumulation (and min energy gradients)
Two competitors, A better than B
Which have more offspring
Which acquired and retains more energy
Which dissipates more low grade energy into universe?
Which more fully meets the demands of the least action universe?
Which will be disproportionally represented in next generation?
Which will support more predators
Which will support more primary producers
All A
