William Hall & Tony Smith
Central Victorian Atheists & Freethinkers
6:30 for 7:30 – 9:00 18 April Albion Hotel, 41 Mollison St, Kyneton
Is anyone out there? Fermi’s Paradox and the Drake
Equation
Contingency vs natural selection in the origin of technologically advanced
self-consciousness
Planet Earth
N = R* • fp • ne • fl • fi • fc • L
Fermi’s paradox
The physicist Enrico Fermi noted the apparent contradiction between high probability estimates for the existence of extraterrestrial civilizations, and the complete lack of evidence that such civilizations exist.
The basic points of the argument are: – Billions of stars in the galaxy are similar to the Sun, and many are billions of
years older than our Solar system.
– With high probability, some of these stars have Earth-like planets, and if the Earth is typical, some may have developed intelligent life.
– Some of these civilizations may have developed interstellar travel or communications, steps humans are investigating now.
– Even at the slow pace of currently envisioned interstellar travel, the Milky Way galaxy could be completely traversed in a few million years. Electronic communications would be even faster.
According to this line of reasoning, the Earthlings should have already been visited by or at least detected the existence of extraterrestrial aliens. In an informal conversation, Fermi noted no convincing evidence of this, leading him to ask, "Where is everybody?”
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Bill Hall: A question I have pondered since childhood
Informed by the diversity of marine life, geology, microscopes, telescopes, and engineering [living on a boat with a geologist father working in the aerospace industry]
Academics: physics, chemistry, ecology, microbiology, physiology, genetics, animal behavior and comparative/structural biology
Research: neuroscience; PhD (cytogenetics, paleontology, biogeography, systematics/taxonomy, speciation, evolution); “biology” and theory of organizations
Professions: – Teaching (invertebrate/marine zoology, vertebrate anatomy/biology,
classical/molecular/cyto—genetics, evolutionary biology)
– Software documentation, document management & computer literacy
– Engineering knowledge management systems analysis and design in the defence industry
“Retirement”: Tracing the coevolution of human cognition and technology (Evolutionary biology of species and organizations) 3
In 1961 the radio astronomer, Frank Drake, developed a logic to estimate how many detectable civilizations might exist in the galaxy
Are humans unique? Are we the only self-conscious technologically competent entities in the galaxy?
The Drake Equation (N = R*•fp•ne•fl•fi•fc•L) provides a framework for exploring this question – N = the number of active, communicative extraterrestrial civilizations
in the Milky Way galaxy – R*, formation rate of stars suitable for developing intelligent life, – fp, fraction of those stars that have planets, – ne, number of planets, per solar system, with an environment suitable
for the emergence of life, – fl, fraction of those planets that actually develop life, – fi, fraction of life bearing planets where intelligence emerges, – fc, fraction of these intelligences that develop technologies that are
detectable from interstellar distances – L, length of time over which such intelligences remain detectable from
interstellar distances
See The Medium’s The Drake Equation Is Broken; Here’s How To Fix It
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What does an “intelligence” have to evolve to be detectable?
Requirements to be detectable – Detectably alter their local stellar environment in a way that
would be detectable from interplanetary distances
– Cross interstellar distances to reach the vicinity of Earth in a detectable way
– Emit detectable signals (electronic?) such that they are detectable by Earthlings.
It is assumed that these requirements would be met by sufficiently sophisticated technologies able to physically manipulate the material and/or electronic worlds to an extent that would be detectable
How probable is this?
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Astronomical variables
R* formation rate of stars suitable for developing intelligent life – Milky Way has many billions
of stars.
– Suitable star must be long-lived and reasonably stable – i.e. on the Main Sequence with a life-time of several billions of years. Dwarf stars below a certain size probably too variable.
– Several billions would qualify
fp fraction of those stars that have planets – Most solo stars and some
stars in multiple systems probably have planets
Ne number of planets per star suitable for the emergence of life – Our solar system has two
planets & several moons offering plausible conditions 6
(Image Credit: Pearson Education, Addison Wesley)
There are plenty of planets to play with e.g., TRAPPIST-1 System
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Dong et al. 2017 estimate our galaxy contains ~10¹º Earth-sized planets within the habitable zones of their stars
More difficult questions: how many planets with life will evolve intelligent life with communicative technologies?
Bill says that given the nature of natural selection and enough time, intelligence will frequently emerge
– However, evolving intelligence will almost inevitably lead to self-extermination
– Answers the Fermi Paradox: Intelligent communicative civilizations don’t last long enough to have a significant chance of being detected
Tony says that the evolution of technologically competent intelligence requires a sequence of many highly improbable contingencies
– The evolution of intelligent communicative civilizations is highly improbable
– Answers the Fermi Paradox: Humans may be the only intelligent civilization now in existence
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Bill’s thesis • Life is an emergent phenomenon inherent in the laws of nature.
• Laws of thermodynamics force systems transporting energy from high potential sources to lower potential sinks to become more organized.
• Complex, self-sustaining, self-reproducing dynamical systems driven by dissipating entropy as they transport energy are living (“autopoietic”)
• Natural selection favors living systems able to more effectively exploit resources of potential energy, however this is achieved.
• Intelligence with the better capacity to anticipate and control perturbations and variable resources will win competitions.
• Selection favors development of tools and technologies to manipulate and control the environment for the tool users’ benefit.
• Evolution is blind, it is based on the history of solved problems, not problems that have not yet arisen
• On a finite planet with limited resources, growth of populations with increasingly powerful technologies will lead to overshoot and dieoff.
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fl = fraction of suitable planets that actually develop life
Answer begins by defining & recognizing life in the most
generic way possible 10
Varela et al. (1974) define life as autopoiesis Reliable knowledge makes systems living
Six criteria are necessary and sufficient for autopoiesis – Bounded
System components self-identifiably demarcated from environment
– Complex Separate and functionally different subsystems exist within boundary
– Mechanistic System dynamics driven by self-sustainably regulated flows of energy
from high to low potential driving dissipative “metabolic” processes
– Self-defining System structure and demarcation intrinsically produced Survival knowledge embodied in instantaneous structure (control
information) or accessibly encoded within the system ( heredity)
– Self-producing (= “auto” + “poiesis”) System intrinsically produces own components
– Autonomous self-produced components are necessary and sufficient to produce the
system.
Autopoiesis is a good definition for life as we know it – Living things are catalysts that are also autocatalytic 11
Autopoiesis (Maturana & Varela 1980; see also Wikipedia) – Reflexively self-regulating, self-sustaining, self-(re)producing dynamic entity
– Continuation of autopoiesis depends on the dynamic structure of the state in the previous instant producing an autopoietic structure in the next instant through iterated cycles where the dynamic structure serves as “control information”
– Selective survival builds “knowledge” as corrective feedback into the system – problem by problem (Popper 1972, 1994) [see also adaptive landscapes]
By surviving a perturbation, the living entity has solved a problem of life Self-producing cellular automata
demonstrate structural knowledge
Living systems survive by solving problems
Constraints and boundaries, regulations determine what is physically allowable
Energy (exergy)
Component recruitment
Materials
Observation
s
Entropy/Waste
Products
Departures
Actions
ProcessesProcesses
"universal" laws governing component interactions determine physical capabilities
The entity's imperatives and goals
The entity's history and present circumstances
HIGHER LEVEL SYSTEM / ENVIRONMENT
SUBSYSTEMS / COMPONENTS
Constraints and boundaries, regulations determine what is physically allowable
Energy (exergy)
Component recruitment
Materials
Observation
s
Entropy/Waste
Products
Departures
Actions
ProcessesProcesses
"universal" laws governing component interactions determine physical capabilities
The entity's imperatives and goals
The entity's history and present circumstances
HIGHER LEVEL SYSTEM / ENVIRONMENT
SUBSYSTEMS / COMPONENTS
Gliders – cycle in 4 steps
Gosper’s Glider Gun cycles in 14 steps
Laws of the Universe: Live cell with 2 or 3 live neighbours lives Dead cell with 3 live neighbours lives All other live cells die
Coupled subsystems in an autopoietic entity
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Metabolism
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Solar visible (high potential)
Infrared + entropy (low potential)
Some cycles may be driven to higher potentials 13
Energy being transported down a potential gradient in a transport cycle can increase the potential in coupled cycles so long as the cyclic system as a whole increases entropy
Emergent cycles (eddies) driven by energy flowing from high potential sources to low potential sinks dissipate entropy
These become autopoietic when they become self-maintaining
Flux along the focal level
Exergy source
Entropy sink
Autocatalytic metabolism
Material cycles
Autopoietic systems
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Selection and evolution in a nutshell
Heritage: “knowledge passed from one generation to the next” – Structural knowledge held in the “adjacent possible”
– Living knowledge learning dynamically held in cognitive system
– Encoded knowledge held in molecular or other durable objects (genes)
– Cultural knowledge able to be transferred/shared among members of a group within generations (memes)
Random variation: mutation and other non-directed heritable changes
Development: construction and growth of the individual as determined by heritage + environment
Selection: biases in reproducing knowledge within and between generations at cellular, individual and group levels of organization
– Natural-: extrinsic biases affecting individuals and groups
– Sexual/cultural-: intrinsic biases in individuals and groups
Adaptation: changes to better fit the environment Evolution: net heritable changes over more than one generation in
lineage or group 15
Link
Link
Link
Define life generically - not just “life as we know it”
Life is a physical phenomenon driven by fluxes of energy from high-potential sources to lower-potential sinks
Selection will cause life to emerge wherever physiochemical conditions allow sufficiently complex physical systems to support autopoiesis (Kauffman 1993. The Origins of Order) — Water-based organic chemistry at the molecular scale offers
limitless opportunities within two broad lifestyles
— I can also imagine life based on other kinds of physical/chemical systems (e.g., electro-magnetic, electro-static, cryogenic)
fl = fraction of suitable planets that actually develop life
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Simple heterotrophic metabolism with cytoplasmic motility
Autotrophic metabolism using stereochemical electron transfers to drive complex synthesis
Life on Earth probably began nearly as soon as it could
Dissipative systems want to live…
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Cantine & Fournier 2017. Environmental Adaptation from the Origin of Life to the Last Universal Common Ancestor
Modular and endosymbiotic origin of eukaryotic cells motility + nucleus + mitochondria + chloroplasts
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Other notable algal symbioses Sponges Cnidaria (corals &
various others) Aceol flatworms Molluscs (clams, sea
slugs) Salamanders
The case for “late” acquisition of mitochondria
Archibald 2016
Archibald 2009
Most people cannot begin to imagine the diversity of life as shaped by the creative power of natural selection
19 Colonial choanoflagellates
Thresholds along the way to multicellularity and differentiation of body plans
Systems of heredity – Structural inheritance implicit in the nature of physical reality
– Living knowledge = tested structural inheritance
– Encoded knowledge = natural selection favors storage of tested knowledge
– Exchanging encoded knowledge = sex (sex reproduction)
Endosymbiosis combining cytoplasmic motility and metabolic power + chemo-/photo-synthesis
Colonial growth/multicellularityModularityDifferential development/spatial specialization (see homeobox and hox)
Sexual & asexual reproductionLife-cycle adaptation/temporal specializationdifferent body plans
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Thresholds for dominating the land
Sensors & effectors: traversing & manipulating the environment – Appendages & development (hox + homeobox ) – Neurosensory + neuromotor cybernetics – Coordinating and managing responses to the environment an inescapable
requirement for living things – For both effectors and cybernetic processing size power
Aquatic organisms unsuited to reach for the stars… – Weightless existence does not select for strength – Water absorbs radiant energy and heat to prevent development of
heat engines and long distance electromagnetic sensors & communication
Moving ashore – Maintaining aqueous environment – Combating gravity – The issue of size/weight and surface area/volume
Developing strength – Animals vs plants – Exoskeletons (hard shells) vs endoskeletons (scaffolds) 21
Arthropod appendages highlight the power of natural selection to explore a phase space
22 Tarsal pad male diving beetle
Swimming appendage planktonic isopod
Freshwater crayfish
Head appendages
Body appendages
Gooseneck barnacle
New set of appendages
fi, fraction of life bearing planets where intelligence emerges
There may be many other pathways to “intelligence” besides ours Earth: steps
– Metabolic power generation, synthesis, storage, & control – Motility/effectors – Systems of heredity – Sensors/sensory cybernetics – Social cooperation at cellular level/organismic/organizational levels – Adequate size and neural complexity – Self-consciousness
Awareness of external environment Awareness of place in it Memory of history Capability to decide and act
– Cooperation/knowledge sharing – Environmental modification – Making tools to extend the body – Making fires to extend the metabolism – Agricultural/scientific/industrial revolution – Making tools to extend cognition, communication & control – Microelectronics revolution & hyperexponential technological evolution 23
Each of these steps can evolve through a sequence of ‘infinitesimal’ changes driven by natural selection
Anticipating problems & developing self-consciousness leads to tool-making, engineering & science
Entities must self-regulate internal fluxes of metabolic energy and materials to live. Cybernetic processes of self-regulation “cognition”
– Physiological/behavioral adaptation (i.e., solving a problem of life) results from self-regulation
– If environmental bounds where self-regulation is possible are exceeded the entity dies and the heritage it carries is not propagated
– Only individuals that have adaptively survived problems leave progeny. Depending on heritability of the solution(s), these progeny will be equipped to survive this kind of problem
“Consciousness” is where self-regulation evolves to self-reflection – Facilitates control of the physical world to protect and regulate internal
metabolism by anticipating needs and controlling external resources
– External world is best controlled by applying knowledge (structural, genetic, and memetic inheritance) + individual learning and sharing
Growing importance of “cultural heritage” (primates/cetaceans/birds)
The emergence and rapid cultural evolution of tools & tool kits – Extending physical reach and mechanical power of the physical body
– Extending metabolic power beyond the physical body (external combustion)
– Extending cognitive power beyond the physical brain (computers) 24
Image forming eyes & associated neurological systems have evolved many times independently (brain proxy)
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Flagellated protozoan Different kinds of flatworms
Pecten (kind of scallop)
snail limpet
squid
Polychaete worms have eyes and “brains” too & have evolved active predators hunting by sight and touch
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Bobbit worm up to 3 m long!
A pelagic raptor with image forming eyes
A generalized 4-eyed predator
Article with videos
Simple choices make the path to consciousness and engineering more-or-less inevitable as long as energy flows through system
Consumer vs synthesizer (high power)
Mobile vs sessile (find/pursue your food)
Size vs numbers (overpower prey and competitors)
Systems for support, locomotion, respiration, circulation, digestion, coordination, sensing and interacting Endoskeleton vs exoskeleton (surface area to volume ratios)
Terrestrial vs aquatic (exploit new niches)
Learning vs anticipating by instinct (cope with rapid change & diversity)
Vertebrates vs social insects
Social vs solitary (cooperate to dominate) – Requires ability to communicate and share knowledge
– Extend body by exploiting environment to make tools
– Niche construction
– Engineering
– Science
Breaking ecological restraints 27
Human populations, knowledge, and technology have been growing exponentially
World population when I was born in August 1939 ~2.3 bn
World population now ~ 7.5 bn; increased ~ 3.4 X in my life 28
History of technology and human population growth
° °
Hyperexponential growth in computing technology
Beyond flat IC’s – 3D IC’s Heat
management
– Biomolecular (e.g., DNA) Speed
Transduction
Interface
– Quantum Heat
management
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Ray Kurzweil 2013
Some conclusions
Where terrestrial life survives long enough, heritable variation and selection ensures intelligent technologically adept civilizations will evolve to dominate planetary resources
Blind natural selection/tragedy of the commons ensures overshoot and collapse
– Increasing fragility to catastrophic die-off
– Major mass extinctions
– Degradation & dispersal of energy and mineral resources makes restarting much harder
How our overshoot is progressing is described in my presentation: The Angst of Anthropogenic Global Warming: Our Species' Existential Risk. Existentialist Society, Unitarian Church, East Melbourne, Tuesday 6 September 2016;
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2015 Meetup on Human Origins, Cognitive Technologies, and Futures explored human evolution and technological growth
Will the exponential growth of human population, knowledge and technology end in a singularity, spike, or an inflected S-curve
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The first option – infinite growth – is impossible The second option – unsustainable exponential
growth followed by a catastrophic climatic/ ecological collapse - is all too likely. This is the path we are on now. The tipping point is not far away if it is not already too late
The third option – a sustainable steady state - may still be possible if we act now
Survival will require deep cultural change from striving for continuous growth to striving for sustainability. This change can only be achieved by political action that requires cooperation to replace competition
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OVER AND OUT
Control information = “structural knowledge” applied via upward and downward causation
System has only one adjacent possible in each next instant
Upward causation = application of the governing rules to individual cells
Downward causation = location on On cells at time instant “Now” determines location of On cells at time instant Now + 1 33
A “glider” system in Conway’s Game of Life “On” cells are black, “Off” cells are empty or gray. Empty “Neighbouring” cells are grey The UNIVERSE is a 2D grid where a cell may be Off or On; The UNIVERSE has three and only three deterministic laws: (1) An Off cell with exactly three on neighbours turns On; (2) An On cell with two or three on neighbours stays On; (3) Cells with other than two or three On neighbours turn Off
or remain Off
What has survived to now greatly constrains what can happen next = structural knowledge
Kauffman’s “adjacent possible” Possible configurations of state
space that may exist in the next instant from “now”
Only one of these crystallizes in the next instant – which then provides the cause for forming the next future state.
Each step in the advance of time prunes all but one adjacent possible configuration
The only possible configurations for further change are those adjacent to the realized state – These will be an infinitesimal
fraction of all possible states of the state space.
– Thus, future states of the system are highly constrained by the history of past states realized by the system 34
Trajectory of a particle through space and time where the motion is randomly perturbed. (After Ellis 2006b; Ellis & Rothman 2010). t1 and t2 represent different instances of becoming or “nows”. The trajectory in the past either no longer exists or cannot be changed, and the possible future trajectories don’t exist until they are realized or crystallized in the continually iterating now.
microfossils suggest methanogen–methanotroph communities were significant in the Paleoarchean biosphere 3,465 Ma
35 J. William Schopf et al. PNAS 2018;115:1:53-58
Niche shifts Survival probability of particular phenotypes
Mutation is blind – selection drives evolution
Niche shift: Natural selection tracks current requirements, generally with continuing specialization and does not anticipate the future
Niche expansion: Retain original adaptation together with adding new capabilities, i.e., accumulation or (very rare) cases of gene duplication and functional divergence
Grade Shift: New mutation may cross adaptive threshold opening new adaptive landscape (i.e., grade shift)
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Niche shift
median phenotype moves across
adaptive landscape
Niche expansion
greater success at environmental
extremes
(+) (+) (-) (+)
Normalizing
selection maintains status quo
Ultrastructure of a paramecium pellicle
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Fascinating to see just how complex and diverse single-celled organisms can be. A classical text: THE CILIATED PROTOZOA Characterization, Classification and Guide to the Literature SECOND EDITION (1979) JOHN O. CORLISS
Some talking points
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Echinoderm larvea
Most marine worms have two pairs of eyes in the head segment. In developing Fabricia sabella segmentation splits the pairs sending one pair of eyes to the pygidium (anal segment). Escape behavior is led by the tail!
Dipleurula larva similar to polychaete tornaria larva but development to adult is very different
Tarsal pads of six different diving beetle species
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Enzymes, polymers, & autocatalytic systems (Kauffman 1993 - Origins of Order)
One mole = 6.022140857×1023 number of particles per mole
Hydrogen atom 1, Carbon atom 12, Oxygen atom 16
Amino acids MW = ~50 – 200 daltons (C = 12)
Nucleotides = ~320 – 550
RNA components of genetic systems
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Enzymatically Active RNAs Molecular Weight (monomers / daltons)
E. coli tRNA: 75 / 2.6 x 10⁴ 5S rRNA: 120 / 4.1 x 10⁴ 16S rRNA: 1541 / 5.2 x 10⁵ 23S rRNA: 2904 / 9.9 x 10⁵ Drosophila 18S rRNA: 1976 / 6.7 x 10⁵ 28S rRNA: 3898 / 1.3 x 10⁶
Mouse 18S rRNA 1869 - 6.4 x 10⁵ 28S rRNA 4712 - 1.6 x 10⁶ Rabbit 18S rRNA 2366 8.0 x 10⁵ 28S rRNA 6333 2.2 x 10⁶ Human 18S rRNA 1868 6.4 x 10⁵ 28S rRNA 5025 1.7 x 10⁶
Cell Biology by the Numbers
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There are 2-4 million proteins per 1 µm3 of cell volume
What Earth-like habitable worlds would be unsuitable for development of interstellar communication?
Hydrogen is ubiquitous, carbon & oxygen among the more common heavy elements – so all planetary systems will have “habitable zones” where liquid water will exist.
Water worlds (i.e., no opportunity to evolve terrestrial life) – Water is an ideal medium for the origin and diversification of life
– Its physical properties would greatly impede the development of heat engines and an industrial revolution based on exploitation of non-biological energy sources High heat capacity
Huge thermal conductivity
– Water’s high conductivity makes it highly absorptive to opaque for the transmission of electromagnetic radiation Precludes radio communication
Limits visual communication to short distances
Highly unlikely a wholly aquatic civilization would ever develop an engineering capability for interstellar communication or space travel 43
