communication inspired by nature

Transcription

communication inspired by nature
5-11-2012
VIRTUAL
DESIGN
COMMUNICATION INSPIRED BY NATURE
LAB
Biomimicry Specialist Program 2012
Andrea Monge Rodriguez
Virtual Design Lab: Discovering Natural Models
FUNCTION:
How does nature attract?
How does nature transfer information?
NATURAL COMMUNICATION TAXONOMY
Attracting prey/
mating partner
Attracting/
Communicating in
symbiotic
relationships
Species Level
System Level
Anglerfish (p2)
Flamingo (p3)
Frog choruses
(p4)
Fireflies (p5)
Cleaner shrimp
(p6)
Plants (p7)
Flowering plants
(p8)
Bromeliads (p11)
Complex Adaptive Systems
Swarm Theory (p13)
o Swarming: flock, schools and herds (p13)
o Swarm Intelligence: ant and bee colonies (p14)
Ecosystem Theory (p21)
o Ecological Specialization
o Resilience vs Efficiency
o
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STRATEGIES:
1. Attracting prey/mating partner
Anglerfish lures prey
Scale: Species
Organism: Anglerfish (Lophius piscatorius)
Strategy: The anglerfish is a carnivorous fish that lives in sandy and muddy
bottoms of the deep ocean, up to a mile below the surface, where light is
scarce. It is an ambush predator that lies half buried on the sediment and uses
a luminous lure to attract prey within the reach of its jaws. The light is generated
by millions of bioluminescent bacteria that live permanently inside the lure.
Abstracted principle: Lure individuals by presenting a desired item, while
hiding the costs.
References:
“Light lures” excerpt from the BBC documentary series: The Blue Planet
– The Deep
Ask Nature: Lure attracts prey: anglerfish
National Geographic Animals: The anglerfish
Fish Base: The Angler
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Communicating health: flamingoes
Scale: Species
Organism: Flamingo (Phoenicopterus)
Strategy: Adult flamingoes range from light pink to bright red and the color is
directly correlated to how much shrimp they are eating. A well-fed flamingo is
more vibrantly colored and thus more desirable to a potential mate.
Abstracted principle: A simple and effective way to advertise the desirability of
an item could be to color code it in function of how well it performs on a chosen
parameter.
References:
Walker, A. 2010. Biomimicry Challenge: IDEO Taps Octopi and Flamingos
to Reorganize the USGBC. Fast Company. Published online May 11 2010.
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Frog choruses advertise for females
© Calimo (Wikimedia Commons) (license: CC by 3.0)
Scale: System
Organism: Frog and toad species
Strategy: In many frogs and toads, males aggregate in large choruses to
advertise for females. The signals they use are conspicuous and long range;
therefore, choruses constitute a classic example of a communication network.
The challenge of communicating in such large choruses is to balance the costs
and benefits of attracting a mate, repelling rivals and avoiding predators and/or
parasites.
The techniques used to overcome this challenge are:
 Increase call repetition rate
 Increase complexity of calls
 Defend calling sites/acoustic space
 Alternate or synchronize their calls with neighboring males (subset of 3 or
4 males)
 Use other communication channels (e.g. vibration)
Abstracted principle: There are a number of techniques that can prevent a
signal being drowned between a large number of similar signals.
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Increase signal repetition rate
Increase the complexity of the signal
Defend a calling space
Collaborate with others to alternate/synchronize signals
Use other communication channels
References:
McGregor, P. 2005. Animal Communication Networks. Cambridge
University Press. Cambride, UK
Firefly choruses attract mates
Scale: System
Organism: Firefly (Pteroptyx)
Strategy: Fireflies are a group of winged beetles which use bioluminescence to
attract mates. The light is produced by a chemical reaction in organs called
lanterns, located in the lower abdomen of the insect. During the courtship process,
firefly use flashes of light, steady glows and chemical signals to communicate with
potential mates.
Tropical male fireflies, in particular, in Southeast Asia, routinely congregate in
mangrove trees, in the river banks, and synchronize their flashes among large
groups. This phenomenon is explained as phase synchronization and
spontaneous order.
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Abstracted principle: By forming congregations and synchronizing signals,
individuals greatly improve the chances that their message will be received by
their target.
References:
Encyclopedia of Life: Lampyridae, Lightning bug
Lewis, S.M., Cratsley, C.K. 2008. Flash Signal Evolution, Mate Choice,
and Predation in Fireflies. Annual Review of Entomology, 53: 293-321
TED: Steven Strogatz: Sync
2. Establishing & maintaining symbiotic relationships
Avoiding predation by providing a service: Cleaner shrimp
Stenopus hispidus © Nick Hobgood (Wikipedia) (license: CC by 2.0)
Scale: Species
Organism: Rebanded Coral Shrimp (Stenopus hispidus)
Strategy: Redbanded coral shrimp are found in reef habitats in tropical waters.
Stenopus hispidus is a “cleaning shrimp.” Individuals remove and consume
parasites, injured tissue and rejected food particles from some coral reef
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organisms. S. hispidus perches near the opening of the cave or ledge in which
they are living and attract fish by their posture, color patterns and their waving
antennae. These locations sometimes become known as cleaning stations.
Individuals have the freedom to enter the mouth and gill cavities of host
organisms, without being eaten, but usually remain in contact with the substrate
when cleaning. Species that S. hispidus has been known to clean include morays,
tangs, grunts and groupers.
Abstracted principle: Individuals that provide a service are conspicuous in order
to advertise their presence and differentiate themselves signaling they are there to
provide a useful service.
References:
Encyclopedia of Life: Redbanded Coral Shrimp (Stenopus hispidus)
Animal Diversity Web (University of Michigan): Stenopus hispidus
Leaves communicate pest damage
Toxin production by leaves (image from BBC documentary “How to grow a planet”)
Scale: Species
Organism: Plants
Strategy: It was recently discovered that plants can communicate through
chemical signals. When a plant is attacked by an herbivore, they start producing
toxins to deter the predator, but they are also able to warn other plants of the
attack. They do this by releasing a chemical signal in the form of a gas from the
leaves. This gas triggers biological activity in neighboring plants which start
producing toxins to protect themselves
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Abstracted principle: Establishing communication networks to communicate a
threat as soon as it is perceived can help collaborators quickly prepare and
respond in a more efficient way than without warning.
References:
How to Grow a Planet: Life From Light. BBC Documentary 2012 (minutes
50:20-53:10)
Collaboration gives flowering plants the competitive edge to take-over a giantdominated planet
Scale: System/Evolution
Organism: Flowering plants
Strategy: Around 400 million years ago, the first plants left the ocean behind
and colonized the land, changing weather patterns, the composition of the
atmosphere and contributing to the creation of nutrient rich soils. In this evolving
and increasingly fertile landscape, animals which had been confined for millions
of years to the rivers and oceans could finally emerge to the land.
Around 230 million years ago, this lead to the evolution of dinosaurs, two thirds
of which were herbivores. For 200 million years, the dinosaurs and plants were
locked into an evolutionary race. Ferns evolved chemical and mechanical
defenses to avoid being eaten, while conifers used wood to grow taller and
taller. At the time of the single super continent Pangea, the earth was
dominated by giants: the sequoias. After several years of allocating most of
their energy to growth, conifers rely on wind to reproduce, blowing male pollen
to a nearby female cone. It is a very wasteful process because in order to
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ensure the gametes will meet up to 10 billion grains have to be released by a
singly tree. Similarly, ferns rely on water to transport their gametes, being
restricted to swampy areas. These limitations meant that the plant kingdom
during Pangea was lacking diversity.
140 million years ago, a random mutation, lead to the evolution of a species of
plant with an innovative reproduction strategy: the amborella plant. Botanists
believe some leaves of this plant to become white petals. Beetles munched on
these petals packed with pollen, but not all the pollen was eaten, some sticks to
the insect’s body and is transferred to another plant. This was the birth of
flowers.
Amborella trichopoda © Scott Zona (Wikimedia Commons) (license: CC by 2.0)
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What followed was a new type of co-evolution based not on predation or
competition but collaboration. In order to attract insects, flowers evolved
different colors, odors and shapes. These adaptations were not random but
evolved to attract specific insects to transfer the right pollen to the right plant.
Animals were lured by these signals and once they reached the flower, they
found nectar, a sugar packed liquid, which became the primary source of food
for many species and ensured they kept coming back to visit the flowers and
carry their pollen. Thus flowers became the evolutionary force behind entirely
new species of animals, such as bees, butterflies, moths, birds, resulting in an
increasing diversity of life.
Back then, the supercontinent of Pangea was splitting up, creating countless
new landscapes with new climates and environments. For conifers and ferns so
reliant on wind and water, the new landscapes were inaccessible; it was the
chance flowering plants were waiting for. Besides having a more efficient
reproductive and dispersal strategy based on cooperation, flowering plants
adapt much faster to new environments. While conifers don’t reach sexual
maturity until they are, on average, 40 years old, most flowering plants mature
in a few months. As a result, in the time it takes to a conifer to produce one
generation, the flowers can go through 120 generations. Every time there is a
new generation there is a chance for genetic mutation, so the faster the life
cycle, the faster can species adapt to new environments.
In hostile environment flowering plants had to evolve mechanisms that enabled
their offspring to survive throughout the year, which leads to yet another
innovation: seeds. By capsuling their offspring in a hard shell with a nutritious
content, flowering plants produced seeds that were able to remain dormant for
months or even years waiting for the right conditions to germinate. Therefore,
65 million years ago, when a 10 km-wide asteroid hit the earth, wiping out most
dinosaurs and plant species, seeds allowed flowering plants to survive. Now,
they needed to spread their seeds across this new barren landscape and
engaged in a second collaborative relationship with a rising group of animals
which replaced dinosaurs: the mammals. Flowering plants ensured mammals
spread their seeds to all kinds of new environments through the evolution of
nutritious fruits. This in change drove the evolution of many animal species. For
instance, most primates have a diet made up mainly of fruits. In order to prevent
mammals from eating fruits before the seeds matured, plants color coded them.
Interestingly, the first primates were color blind, and it was the color of mature
fruits that triggered the evolution of color vision.
Abstracted principle:
Looking at evolution scale processes reveals the fact that we live in a state of
dynamic non-equilibrium, a complex unpredictable environment. In order to
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adapt to constant changes and overcome disruptive shocks, the evolutionary
history of flowering plants can teach us the following strategies:
Diversity – Having a diversity of independent, decentralized forms and
relationships is a key resilience factor in the face of disturbance.
Faster life-cycles – faster turnover of ideas coupled with decentralization lead to
small scale localized changes which can build upon each other and develop
momentum and are much more likely to drive innovation than rigid, resource
intensive, globalized processes.
Optimizing through collaborative relationships – The old communication
paradigm was based on linear, one-way communications that pushed products
to the market, and concentrated on maximizing sales (c.f. sequoias allocating
most energy on maximizing growth). In contrast, the new communication
paradigm, must focus on optimizing cooperative relationships by focusing on
providing outcomes (solutions) rather than products, by being more flexible in
order to adapt to a changing environment.
References:
How to Grow a Planet: The Power of Flowers. BBC Documentary 2012
Bromeliads creates a small community which collectively supply nutrients for
the plant
© edgeplot (Flicker) (license: CC-by-nc-sa - Attribution Non-commercial Share Alike)
Scale: System
Organism: Bromeliads
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Strategy: Bromeliads are epiphytes, plants that grow on tree branches but are
not parasitic; they anchor themselves around wrapping their roots around the
branch without harming their host. Since they can’t access the ground, they
need to capture nutrients in another way. Their long leaves grow in a tight
rosette around their central bud and channel rain water down to it so that the
rosette fills and forms a small pond. This small pond represents a little oasis in
the canopy of the forest attracting all sorts of species and becoming a world in
miniature. Leaves and other bits of vegetable detritus fall into it and decay.
Birds and small mammals come to sip the water, and leave behind their
nitrogen-rich droppings. Microscopic organisms of one kind or another develop
in it, as they will do in any pool of standing water. Mosquitos lay rafts of eggs in
its depths, though in much smaller numbers. In due course, a few dragonfly
larvae will feed on a multitude of mosquito larvae. Small brilliantly colored frogs
that live nowhere else but in bromeliad ponds take up residence and spawn
there. Crabs, salamanders, slugs, worms, beetles, lizards, even small snakes
may all join the community. All these animals release valuable nutrients into the
pond that the bromeliad can uptake to survive.
Abstracted principle: Provide individuals with outcomes which are rare in their
environment to attract them and form a community centered on those
outcomes.
References:
Ask Nature: Epiphytes capture nutrients: Bromeliads
Attenborough, D. 1995. The Private Life of Plants: A Natural History of
Plant Behavior. London: BBC Books. 320 p.
Kew Gardens: Epiphytes – Adaptations to an aerial habitat
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3. Complex adaptive systems
SWARM THEORY
Swarming
Swarming is a collective behavior exhibited by animals of similar size who
aggregate together either in a fixed area or while migrating. As a term,
swarming is applied particularly to insects, but can also be applied to any other
animal that exhibits swarm behaviour. The term flocking is usually used to refer
specifically to swarm behaviour in birds, herding to refer to swarm behaviour in
quadrupeds, shoaling or schooling to refer to swarm behaviour in fish.
As members of a big group, whether it's a flock, school, or herd, individuals
increase their chances of detecting predators, finding food, locating a mate, or
following a migration route. For these animals, coordinating their movements is
crucially important. They do so in a decentralized manner, there is no leader.
Instead, each individual interacts with its environment following three simple
rules:
1. Separation - avoid crowding neighbors (short range repulsion)
2. Alignment - steer towards average heading of neighbors
3. Cohesion - steer towards average position of neighbors (long range
attraction)
If every individual follows these rules, the combination of their interactions results
in complex adaptive patterns by the group that would be impossible to
choreograph.
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Swarm Intelligence
Swarm intelligence is the collective decision-making observed in social insects
such as ants, bees and termites. Individual within a colony have meager
intelligence and work without a vision of the whole system. Yet collectively, they
achieve surprisingly complex and effective results, such as building termite
mounts or finding the most efficient paths to food sources. This all occurs in a
decentralized, self-organized system coordinated through simple interactions
between individual members of the colony.
Eric Bonabeau and Christoph Meyer (2001) argue that there is much to learn from
the social insects’ main behavioural features:
Flexibility: the group can quickly adapt to a changing environment.
Robustness: even when one or more individuals fail, the group can still
perform its tasks.
Self-organisation: the activities are neither centrally controlled, nor locally
supervised but emerge from collective interactions
Ant colony optimization: increasing foraging efficiency through communication
and cooperation
© Julian Szulc (Wikimedia) license: cc by 3.0
Scale: Species
Organism: Pharaoh ant (Monomorium pharaonis)
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Strategy: Many ant colonies form networks of foraging trails, a system that
requires communication and cooperation of the individuals within the colony. To
ensure efficient foraging, the colony must send foragers to food sources, which
are constantly changing in terms of location. Once an ant finds a food source, it
needs to communicate the location to other foragers. Ants use two
mechanisms, they either lead recruits directly or they use pheromone trails.
Initially, an ant wanders randomly, upon finding food, it leave a pheromone trail
as it returns to the colony. If other ants find the trail, they are likely to stop
traveling at random and follow the path to the food source. These ants, in turn,
leave their own trails. However, over time trails start to evaporate, reducing their
attractive strength. The longer it takes for ants to travel up and down the path,
the more likely the pheromones will evaporate. As a consequence, shorter
paths get marked more frequently, increasing the pheromone density. This
positive feedback eventually leads all the ants to follow a single, efficient path.
Ant colony optimization model
1. The first ant finds the food source (F), via any way (a), then returns to the nest (N),
leaving behind a trail pheromone (b)
2. Ants indiscriminately follow four possible ways, but the strengthening of the
runway makes it more attractive as the shortest route.
3. Ants take the shortest route, long portions of other ways lose their trail
pheromones.
Moreover, in the case of Pharaoh ants foragers use two type of trails, positive
and negative feedback trails. Positive feedback trails are created after an ant
finds food and deposits pheromone on its way back to the nest in order to signal
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the path to other ants in the colony. In contrast, negative feedback trails occur
when ants mark an unsuccessful or depleted trail with a repellent trail
pheromone. As a result, the trail network from the entrance of the nest does not
direct foragers to random locations, but to the best feeding locations.
The key to the success of the ant colony foraging strategies is the selforganization of multiple agents. The success of the foraging network emerges
from simple actions performed individually by each worker ant in response to
local conditions, while being unaware of the cascading effect that action has on
the overall colony.
References:
Bonabeau, E., Meyer, C. 2001. Swarm Intelligence: a whole new way to
think about business. Harvard Business Review, May 2001: 107-114
Ratnieks, F.L.W. 2008. Biomimicry: Further Insights from Ant Colonies?
In Liò, P., Yoneky, E., Crowcroft, J., Verma, D.C. (eds). Bioinspired
Computing and Communication (pp 58-66). First Workshop on BioInspired Design of Networks, BIOWIRE: Cambridge, UK April 2007.
Robinson, E.J.H., Jackson, D.E., Holcombe, M., Ratnieks, F.L.W. 2005.
‘No entry signal’ in ant foraging. Nature (438): 442.
Encyclopedia of Life: Pharaoh ant
Organization and task division in red harvester ants
© Steve Jurvetson (Wikimedia) license: cc by 2.0
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Scale: System
Organism: Red harvester ants (Pogonomyrmex barbatus)
Strategy: Each morning, colonies of red harvester ants calculate the number of
foragers to send out based on local conditions. Early morning patrollers go out to
look for food, when any given patroller encounters food, it comes back to the nest
and communicates it to the foragers by touching antennae. However, the forager
will not go out immediately, it will wait until it has several contacts with different
patrollers no more than 10 seconds apart. Foragers use the rate of their
encounters with patrollers to tell if there is enough food and if it's safe to go out.
Once the ants start foraging and bringing back food, other ants join the effort,
depending on the rate at which they encounter returning foragers.
Moreover, harvester ants show another strategy to make foraging more
efficient. When they locate a good source of food, red harvester ants pass the
seeds down a chain all the way to their nest. However, unlike runners in a relay
race, the ants are not stationary, and their transfer points are not fixed: an ant
takes the seed until the next ant, transfers the food, and then goes back until it
meets the previous ant in the chain to receive the next seed. The only fixed
points in this process are the source of the food and the nest. This approach,
known as the “bucket brigade” dramatically increases efficiency by preventing
slower individuals to delay faster ones.
References:
Bonabeau, E., Meyer, C. 2001. Swarm Intelligence: a whole new way to
think about business. Harvard Business Review, May 2001: 107-114
Peter Miller. 2007. The Genius of Swarms. National Geographic: June
2007
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Group decision making in honeybee swarms
© Thomas D. Seeley published in Seeley et al. (2006)
Scale: System
Organism: Honeybees (Apis mellifera)
Strategy: One of the best examples of communication and decision making in
animal group is the nest selection process of swarms of up to 10,000 bees.
When a bee colony becomes too large – that is when it reaches a point of
diminishing returns – bee colonies split themselves in a process known as
swarming, where approximately half of the hive follows the queen to establish a
new colony, while the rest stays in the old hive with the daughter queen to
perpetuate the old colony.
After living the hive, the newly formed swarm forms a beardlike cluster in a
neighboring branch and starts the nest selection process. The colony then
delegates the task of finding a new nest to a few hundred scouts. The other
bees remain quiescent during the process to conserve energy. The entire
process lasts a few hours. At first, the scout bees leave in random direction in
search of potential nesting sites. Once they find an option, they return to the
colony and perform a waggle dance to advertise her site. The pattern of the
dance indicates the direction and distance to the site (Figure 3), while the
intensity of the waggle dance is proportionate to the quality of the site found.
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© Seeley et al. (2006)
The intensity of the waggle dance is also proportionate to the number of times a
scout will to go to her chosen site and back to the colony (a circuit). As a result,
over time, a larger number of advocates remain for the stronger sites.
Moreover, the number of scouts can also increase by recruiting those scouts
who did not find a site. While these uncommitted scouts tend to follow the ones
with the greater strength of dancing, they will not advocate for the site until they
have seen it and assessed it for themselves. Once the number of scouts
advocating for a particular site reaches a threshold number, the entire colony
takes off towards the site of its new nest.
Therefore, the essence of a swarm's decision making lies in sensing a quorum
(sufficient number of scouts) at one of the nest sites rather than sensing a
consensus (agreement of dancing scouts) at the swarm cluster.
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© Seeley et al. (2006)
Abstracted principle: Seeley et al. (2006) argue there are three key factors
that underline the efficiency of the honeybees communication model and ensure
the effectiveness of their group decision strategy.
1. Decentralized organization: the individuals are organized in a way that
allows diversity of knowledge within the group. They are not lead or
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dominated by a small number of individuals, instead the decision making
process is based on the actions of hundreds of individuals, each one
providing autonomous information which is freely reported.
2. Non-conformity: the individuals show no tendency towards imitation.
Uncommitted individuals will follow the strongest signals towards the
advertised site, but they will assess the site for themselves before
deciding if they will advocate for it. Through this independence of
opinions the individuals propagating errors in the assessment of sites.
3. The quorum sensing process aggregates the diverse and independent
opinions of individuals in a way that balances the competing needs of
accuracy and speed of the decision making process.
References:
Seeley, T.D., Visscher, P.K., Passino, K.M. 2006. Group decision making
in honeybee swarms. American Scientist, 54: 220-229
ECOSYSTEM THEORY
Ecological specialization
The concepts of specialist versus generalist species have a long history both
in theoretical and applied ecology. Ecological specialization is intrinsically linked
to the ecological niche concept, which is most often defined by Hutchinson
(1975) as a hyper-volume in the multidimensional space of ecological variables
(resources, predators, competitors, etc.), within which a species can maintain a
viable population. An organism free of interference from other species could use
the full range of conditions (biotic and abiotic) and resources in which it could
survive and reproduce which is called its fundamental niche. However, as a
result of pressure from, and interactions with, other organisms (i.e. competition)
species are usually forced to occupy a niche that is narrower than this, and to
which they are mostly highly adapted. This is termed the realized niche.
A generalist species is considered to have a wide niche breath; it is able to
thrive in a wide variety of environmental conditions and can make use of a
variety of different resources (for example, a heterotroph with a varied diet). In
contrast, a specialist species can only thrive in a narrow range of environmental
conditions or has a limited diet. In stable environment, with high diversity and
abundant resources, specialists are more frequent. Being a specialist, allows
species to perform tasks more efficiently. However, when environmental
conditions change, generalists adapt more easily, they are more resilient. As a
general trend, specialist species are increasingly shown to be declining and
experiencing higher extinction risk relative to generalist species (Devictor et al.,
2010).
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Nevertheless, this trade-off between efficiency and resilience depends on the
scale in which we study a species as well as on the context.
Scale: Leaf-cutter ants
Let’s look at scale first: leaf-cutter ants (Atta sp) are not herbivores and yet we
can encounter lines of ants cutting leaves and carrying them back to their nest.
In fact, what the ants are doing is farming. Foragers take the leaves into the
nest and transfer them to worker ants which chew the leaves and turn them into
a pulping mulch they then feed to a fungus. The fungus breaks down the
proteins in the leaves and swells with proteins and sugar the ants can feed on.
© Wikipedia.org (license: CC-BY-SA-3.0)
The ants farm a single species of fungus (Leucoagaricus gongylophorus) that
grows nowhere else but inside leaf cutter ants’ nests. In this sense, at a large
scale, leaf cutter ants are very efficient at growing a monoculture. From our own
experience as human farmers we know monocultures are less resilient than
polycultures since a single pest or bacteria can have detrimental effects on the
entire crop. Not surprisingly, the gardens of fungus-growing ants are host to a
specialized, virulent, and highly evolved fungal pathogen in the genus
Escovopsis. However, in spite of these pathogens, the gardens farmed by ants
have proven quite resilient over millions of years. Even though leaf cutter ants
are efficient specialists at a large scale, at a smaller scale, ants have evolved a
mutualistic association with filamentous bacteria (actinomycetes) that produce
antibiotics that suppress the growth of Escovopsi.
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References:
Barke, J., Seipke, R. F., Gruschow, S., Heavens, D., Drou, N., Bibb, M. J.,
Goss, R. J. M., Yu, D. W. and Hutchings, M. I. 2010. A mixed community of
actinomycetes produce multiple antibiotics for the fungus farming
ant Acromyrmex octospinosus. BMC Biology 8, 109.
BBC Living Planet : Fungus Gardeners
Currie, C.R. 2001. A Community of Ants, Fungi, and Bacteria: A Multilateral
Approach to Studying Symbiosis. Annu. Rev. Microbiol. 55: 357–80
Devictor, V., Clavel, J., Julliard, R., Lavergne, S., Mouillot, D., Thuiller, W.,
Venail, P., Villéger, S., and Mouquet, N. 2010. Defining and measuring
ecological specialization. Journal of Applied Ecology 47: 15–25
Hutchinson, G.E. 1965. The ecological theatre and evolutionary play.
Yale University Press, New Haven, Connecticut, USA.
Context: mixed species flocks
The trade-off species make between resilience and efficiency also depends on
the context and it has been shown that when conditions change and a threat
arises or resources are limiting, some species tend to be more generalist and
show increased cooperation. A good example of this is mixed species flocks.
© Chuq Von Rospach. License: BY NC ND
It is not uncommon to find birds of several species flocking together. In the Eastern
forests of North America, mixed flock species are formed during winter. These
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flocks are composed by two groups: nuclear species, such as tufted titmouse and
chickadees, which facilitate flock formation and initiate movements; and follower or
satellite species, such as downy woodpeckers and white-breasted nutcracker.
Followers tend to be smaller, more insectivorous, and feed in higher strata than
matched species that participate in flocks to a lesser extent.
Morse (1969), the author showed that mixed flocking is an effective adaptation to
difficult conditions. During winter, less food is available and in eastern deciduous
forests, trees lose their leaves, birds more exposed to predators. Species that are
vulnerable to predation follow species whose vigilance they can exploit. By doing
so, they are able to reduce their own vigilance and forage at higher rates. Indeed,
the two main hypotheses that have been proposed to explain the formation of
mixed-species flocks is an improved feeding strategy and decrease predation risk.
On one hand, having more individuals searching for food increases the likelihood
that a rich feeding patch will be located. In single species flocks, as the number of
individual increases, there is more competition for resources. In contrast, mixedspecies flocks partition resources, minimizing competition. Moreover, by moving
together in a mixed-species flock, birds can avoid areas that have already been
searched for food. Individuals in mixed flocks can also learn about new food
sources from other species. For instance some species have been shown to feed
on insects flushed by other birds in the course of feeding (commensal feeding).
On the other hand, flocking may decrease predation risk by increasing the number
of eyes and ears available to detect predators and may confuse them as many
individuals flee at once. Also a mixture of species can take advantage of different
abilities. For instance, nearsighted gleaning birds such as Red-eyed Vireos move
in groups (on their tropical wintering grounds) with farsighted salliers like Yellowmargined Flycatchers. The former lose some prey to the latter, but apparently are
more than compensated by the latter's early detection of approaching danger.
Similarly, it has been shown experimentally that chickadees and titmice are used
as sentinels by Downy Woodpeckers foraging in mixed-species flocks.
References:
Dolby, Andrew & TC Grubb. 2000. Social Context Affects Risk Taking by
a Satellite Species in Mixed-Species Foraging Groups. Behavioral
Ecology 11(1): 110-114
Erlich, P.R., Dobkin, D.B., and Wheye, D. 1988. Mixed species flocking.
Retrieved on September 28th 2012 from the Stanford University Website:
http://www.stanford.edu/group/stanfordbirds/text/essays/MixedSpecies_Flocking.html
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Goodale, E., Beauchamp, G., Magrath, R., Nieh, J.C., Ruxton, G.D.
Interspecific information transfer influences animal community structure.
Trends in Ecology & Evolution 25 (6): 354-361.
Morse, Douglas H. 1970. Ecological Aspects of Some Mixed-Species Foraging Flocks of
Birds. Ecol Monogr 40: 119-168.
Sridhar, H., Beauchamp, G., Shanker, K. 2009. Why do birds participate
in mixed-species foraging flocks? A large-scale synthesis. Animal
Behaviour 78: 337–347
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BIOMIMICRY RESOURCES
To learn more about Biomimicry:
WEBSITES
Ask Nature (http://www.asknature.org/) AskNature is a free, open source
project, built by the community and for the community. Our goal is to
connect innovative minds with life's best ideas, and in the process,
inspire technologies that create conditions conducive to life. To
accomplish this, we're doing something that has never been done—
organizing the world's biological literature by function.
Biomimicry 3.8 (http://biomimicry.net/) Biomimicry 3.8 is the global
leader in biomimicry innovation consulting, professional training, and
educational program and curricula development. Our mission is to train,
equip, and connect engineers, educators, architects, designers, business
leaders, and other innovators to sustainably emulate nature’s 3.8 billion
years of brilliant designs and strategies.
Biomimicry for Creative Innovation (BCI)
(http://www.businessinspiredbynature.com/) BCI is a network of creative
innovators, professional change agents, biologists and design
professionals who work in creative collaboration with each other and our
clients to apply ecological thinking for radical transformation. At the heart
of our work is a shared passion for creating brilliant, resilient, values-led
human systems that are aligned with nature’s ecosystems. It's what we
call Business Inspired by Nature.
Fast Company Biomimicry Section
(http://www.fastcompany.com/section/biomimicry)
GreenBiz: The Biomimicry Column by Tom McKeag
(http://www.greenbiz.com/business/engage/featured-blogs/thebiomimicry-column)
Zygote Quarterly (http://zqjournal.org/) Our mission is to establish a
credible platform showcasing the nexus of science and design in the field
of biologically inspired design, using case studies, news and articles that
are exemplary in their impact on the field, rigorous in their methodology,
and relevant to today’s reader.
BOOKS
Architecture
Biomimicry and Architecture. Michael Pawlin. 2011. Explores the
application of biomimicry to architecture.
Design for Life. Sim Van Der Ryn. 2005. Van der Ryn explores how
architecture has created physical and mental barriers that separate people
26
from the natural world, and how to recover the sould of architecture and
reconnect with our natural surroundings.
Biology/Evolution
Animal: The Definitive Visual Guide to the World’s Wildlife. Don E.
Wilson. 2001. Over 2,000 species, from the tiny spider mite to the massive
blue whale, are profiled in DK’s astonishingly wonderful Animal, produced in
cooperation with the Smithsonian Institution and more than 70 expert
zoologists
Extreme Nature. Mark Carwardine. 2005. Interesting facts and figures
about some of the most interesting natural phenomenons on earth. From
the “most devious plant” to the “strangest nesting material” this book is
packed full of interesting information about both common and uncommon
organisms.
The Future of Life. Edward O. Wilson. 2002. A great “state of the planet”
survey circa 2002 covering species extinctions and the environment.
Weird Nature. John Downer. Firefly Books. 2002. Some of the most
fantastic behaviors of real animals are explored in this beautifully illustrated
companion volume to a BBC/Discovery Channel series.
Survival Strategies: Cooperation and Conflict in Animal Societies.
Raghavendra Gadagkar. 1997. Why creatures great and small behave in
such fascinating and seemingly perplexing ways is explained in this
delightful account of the evolutionary foundations of animal social behavior.
The Ghosts of Evolution: Nonsensical Fruit, Missing Partners, and
Other Ecological Anachronisms. Connie Barlow. 2002. How surviving
plants are clues to vanished ecological relationships. For designing systems
for humans and animals.
Design
Cat’s Paws and Catapults: Mechanical Worlds of Nature and People.
Steven Vogel. 1998. Investigates whether nature or human design is
superior and why the two technologies have diverged so much.
Cradle to Cradle: Remaking the Way we Make Things. William
McDonough and Michael Braungart. 2002. An engaging description of the
problem with today’s industrial patterns, and a fascinating description of
how a truly sustainable, biomimetic industrial ecology would work.
Decoding Design: Understanding and Using Symbols in Visual
Communication. Maggie Macnab. 2008. Symbols are intuitive and
immediate. Design that references these symbols creates an immediate
relationship with the viewer.
Design for the Real World, Human Ecology and Social Change. Victor
Papanek. 1984. One of the world’s most widely read books on design.
Author provides a blueprint for sensible, responsive design.
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Design in Nature How the Constructal Law Governs Evolution in
Biology, Physics, Technology, and Social Organization. Adrian Bejan.
2012. Everything—from biological life to inanimate systems—generates
shape and structure and evolves in a sequence of ever-improving designs
in order to facilitate flow. All are governed by the same principle, known as
the Constructal Law, and configure and reconfigure themselves over time to
flow more efficiently. Written in an easy style that achieves clarity without
sacrificing complexity, Design in Nature is a paradigm-shifting book that will
fundamentally transform our understanding of the world around us.
Green Graphic Design. Brian Dougherty. 2009. Breaking down the
concept of “green design” step-by-step, respected industry leader Brian
Dougherty captures the ability of designer to communicate, persuade, and
ultimately spread a socially and ecologically responsible message to both
consumers and corporations.
Mental Models: Aligning Design Strategy with Human Behavior. Indi
Young. 2008. There is no single methodology for creating the perfect
product – but you can increase your odds. One of the best ways is to
understand users’ reasons for doing things. Mental Models gives you the
tools to help you grasp, and design for, those reasons.
The Information Design Handbook. Jenn Visocky O’Grady. 2008.
Inspirational gallery of designs that illustrate how to communicate at a
glance, logically, effectively, and with maximum benefit. Includes milestones
from the history of information design that illustrate and explain
breakthroughs and trends.
Economics/Business
Confessions of a Radical Industrialist: Profits, People, Purpose –
Doing Business by Respecting the Earth. Ray C. Anderson. 2009.
Ecology of Commerce. Paul Hawken. 1993. Ecological analysis of
business. Practical suggestions.
In Our Every Deliberation: An Introduction to Seventh Generation.
Jeffrey Hollender. 2009.
Natural Capitalism. Paul Hawken, Armory Lovins, L. Hunter Lovins. 1999.
The original comprehensive treatise on business sustainability, using
numerable examples and case studies. Excerpts available online at
www.natcap.org
Out of Control. Kevin Kelly. 1994. How a new understanding of biology is
transforming both ecology and economics.
The Living Company. Arie de Geus. 1997. The author summarizes the
components of the long-lived company as sensitivity to the environment,
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cohesion, identity, tolerance and decentralization, and conservative
financing.
The Nature of Business. Giles Hutchins. 2012. This book sets out a new
business paradigm. Author Giles Hutchins focuses on the emergence of
new ways of operating and creating value in an increasingly volatile and
interconnected world. He makes the compelling case that the 'Firm of the
Future' should seek to mimic behaviours and organisations found in nature,
which offer fitting models for businesses capable of flourishing in chaotic
and uncertain times.
Innovation
Alternative Pathways in Science and Industry: Activism, Innovation,
and the Environment in an Era of Globalization. David J. Hess. 2007.
Hess identifies alternative pathways by which social movements can
influence scientific and technological innovation.
Bulletproof Feathers: How Science Uses Secrets to Design CuttingEdge Technology. Robert Allen. 2010.
The Gecko’s Foot: Bio-inspiration, Engineering New Materials and
Devices from Nature. Peter Forbes. 2005. Presents technologists’ pure
research into nano-anatomy, followed by their applied and, as many
entrepreneurs hope, commercial mimicry of nature’s ingenuity.
Patterns/Systems Science
The Self-Made Tapestry: Pattern Formation in Nature. Philip Ball. 2001.
This deep, beautiful exploration of the recurring patterns that we find both in
the living and inanimate worlds will change how one thinks about everything
from evolution to earthquakes.
Emergence: The Connected Lives of Ants, brains, Cities, and
Software. Steven Johnson. 2001. Details of the development of
increasingly complex and familiar behavior among simple components.
The Smart Swarm: How Understanding Flock, Schools, and Colonies
can Make us Better at Communicating, Decision Making, and Getting
Things Done. Peter Miller. 2010. Introduces many examples of the wisdom
to be gleaned about the behavior of crowds-among critters and corporations
alike.
The Web of Life: A new Scientific Understanding of Living Systems.
Fritjof Capra. 1996. Capra sets forth a new scientific language to describe
interrelationships and interdependence of psychological, biological,
physical, social and cultural phenomena – the “web of life”. Capra provides
extraordinary new foundation for ecological policies that will allow us to
29
build and sustain communities without diminishing the opportunities for
future generations.
Thinking in Systems: A Primer. Donella Meadows. 2008. Just before her
death, scientist, farmer and leading environmentalist Meadowns (19412001) explains the methodology – systems analysis – she used in her
ground-breaking work and how it can be implemented for large-scale and
individual problem solving.
Thriving Beyond Sustainability: Pathways to a Resilient Society.
Andres R. Edwards. 2010. Draws a collective map of individuals,
organizations, and communities from around the world that are committed
to building an alternative future – one that strives to restore ecological
health; reinvent outmoded institutions; and rejuvenate our environmental,
social, and economic systems.
Turbulent mirror. John Briggs and David Peat. 1989. The authors explore
the many faces of chaos and reveal how its laws direct most of the
processes of everyday life and how it appears that everything in the
universe is interconnected – discovering an “emerging science of
wholeness”.
Sync: How Order Emerges From Chaos In the Universe, Nature, and
Daily Life. Steven Strogatz. 2012. Steven Strogatz, a leading
mathematician in the fields of chaos and complexity theory, explains how
enormous systems can synchronize themselves, from the electrons in a
superconductor to the pacemaker cells in our hearts. He shows that
although these phenomena might seem unrelated on the surface, at a
deeper level there is a connection, forged by the unifying power of
mathematics.
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