Presentation by Emanuele Serrelli ISHPSSB July 2011, Salt Lake City, Utah http://www.conferences.utah.edu/ishpssb/index.html Session: Hierarchy Theory of Evolution Disentangling ecological vs. genealogical dimensions is a core task of hierarchy theory in evolutionary biology. As Eldredge repeatedly epitomized, organisms carry out (only) two distinct kinds of activities: they survive, and they reproduce. ! At the organismal level, the organism stays the same whether we consider it ecologically or genealogically - yet, differences can occur in what features we consider relevant, and what fitness measurement we use. ! At higher levels, the two dimensions diverge, realizing different systems. Reproductive (deme) may not coincide with ecological (avatar) population. Further upwards, along the ecological dimension, higher-level systems are grouped by energy- matter interconnection, whereas, along the genealogical dimension, higher taxa are assembled by relatedness. ! In Dobzhansky's (1937) use of the adaptive landscape visualization (Wright 1932), all living species are imagined as distributed on adaptive peaks which correspond to ecological niches in existing environments. Peaks are grouped forming genera and higher taxa (e.g., "feline", "carnivore" ranges), and geographic speciation is figured out - like adaptation - as movement on the landscape. ! In criticizing Dobzhansky's landscape, Eldredge wrote that species actually do not occupy ecological niches; demes don't, either; avatars do. ! I point out that neighborhood and movement need to be conceived separately in genealogical and ecological spaces. Indeed, ecology should be further split in at least two spaces: geographic and phenotypic/adaptive. Movement in one space may in fact result in stability in the other(s). ! I also comment on the adaptive landscape: technical limitations prevent it from being coherently used above the population level, even though as a metaphor. Finally, I emphasize the partiality of any landscape - based on the choice of relevant features and fitness components - and interpret partiality as the way of approaching complex multi- hierarchical structure in evolution.

1. Hierarchy Theory of Evolution
• Dan BROOKS - Metaphors for the Extended Synthesis: Something Old, Something New.
• Silvia CAIANIELLO - Modularity and Hierarchy Theory.
• Linnda CAPORAEL - Grounding Human Social Cognition in Hierarchical Group Structure.
• Telmo PIEVANI - The Evolving Structure of Evolutionary Theory: the role of Hierarchy Theory for an
Extended Evolutionary Synthesis.
• Niles ELDREDGE - A Matter of Individuality: Hierarchy Theory at the Dawn of Evolutionary Biology.
• Ilya TËMKIN - Nested Networks and Biological Diversification.
• Keynyn BRYSSE – Lessons from Interdisciplinary (Non-) Communication in the Mass Extinction Debate.
• Emanuele SERRELLI - Criticizing Adaptive Landscapes and the Conflation Between Ecology and
Genealogy.
• Gregory DIETL- Toward a Unified Ecology in Macroevolution.
• William MILLER - Macroevolutionary Consonance and expansion of the Modern Synthesis.
1

2. Criticizing adaptive landscapes and the conflation
between ecology and genealogy
Emanuele Serrelli
University of Milano Bicocca, Italy
2

3. Criticizing adaptive landscapes and the conflation
between ecology and genealogy
• There are habits of thinking evolution that have to
do with conflating ecology and genealogy, and they
can lead to inconsistencies in our thoughts.
• Dobzhansky’s (1937) famous version of the adaptive
landscape is a good instance of this conflation.
• But, the tendency to conflate seems to be more
general and lasting (independently from
Dobzhansky’s work, and/or shaped by foundational
works in the Modern Synthesis, among which
Dobzhansky’s influent ideas).
• Method: direct citations and comments
3

4. Niles Eldredge - 40 years of evolutionary critique
4

5. Niles Eldredge - 40 years of evolutionary critique
• 1972 (with Steve Gould) - “Puctuated equilibria: an alternative to phyletic gradualism”,
Models in Paleobiology
• 1984 (with Stan Salthe) - “Hierarchy and evolution”, Oxford Surveys in Evol. Biol.
• 1985 - Unfinished Synthesis. Biological Hierarchies and Modern Evolutionary Thought
(OUP)
• 1989 - Macroevolutionary Dynamics. Species, Niches, and Adaptive Peaks (McGraw-
Hill)
• 1992 (with Marjorie Grene) - Interactions. The Biological Context of Social Systems
(CUP)
• 1995 - Reinventing Darwin (Wiley)
• 1999 - The Pattern of Evolution (Freeman)
• 2008 - “Hierarchies and the Sloshing Bucket: Toward the unification of evolutionary
biology”, Evolution: Education & Outreach
• 2008 - “Some thoughts on ‘adaptive peaks’, ‘Dobzhansky’s dilemma’ - and how to
think about evolution”, Evolution: Education & Outreach
5

6. Criticizing adaptive landscapes and the conflation
between ecology and genealogy
• There are habits of thinking evolution that have to
do with conflating ecology and genealogy, and they
can lead to inconsistencies in our thoughts.
• Dobzhansky’s (1937) famous version of the adaptive
landscape is a good instance of this conflation.
• But, the tendency to conflate seems to be more
general and lasting (independently from
Dobzhansky’s work, and/or shaped by foundational
works in the Modern Synthesis, among which
Dobzhansky’s influent ideas).
• Method: direct quotations and comments
6

7. Different versions of adaptive landscapes:
interesting issues
Theodosius Dobzhansky Sewall Wright
(1937) (1932)
7

8. Dobzhansky’s adaptive landscape (1937)
8

9. Dobzhansky’s adaptive landscape (1937)
• «In an organism possessing only 1000 genes each
capable of producing ten allelomorphs, the number of
the possible gene combinations that may be formed is
101000. Some, probably a great majority, of these
combinations are discordand and have no survival value,
but still very numerous ones may be supposed to be
harmonious in the different ecological niches of the same
environment, as well as in different environments. If the
entire ideal field of possible gene combinations is graded
with respect to adaptive value, we may find numerous
“adaptive peaks” separated by “valleys”. The “peaks”
are the groups of related gene combinations that make
their carriers fit for survival in a given environment; the
“valleys” are the more or less unfavourable gene
combinations. Each living species or race may be
thought of as occupying one of the available peaks in the
field of gene combinations» (Dobzhansky 1937 p. 187; cf.
Wright 1932 p. 356, Eldredge 1985 p. 27).
9

10. Dobzhansky’s adaptive landscape (1937)
• «In an organism possessing only 1000 genes each
capable of producing ten allelomorphs, the number of
the possible gene combinations that may be formed is
101000. Some, probably a great majority, of these
combinations are discordand and have no survival value, genetic map
but still very numerous ones may be supposed to be
harmonious in the different ecological niches of the same
environment, as well as in different environments. If the
entire ideal field of possible gene combinations is graded
with respect to adaptive value, we may find numerous
“adaptive peaks” separated by “valleys”. The “peaks”
are the groups of related gene combinations that make
their carriers fit for survival in a given environment; the
“valleys” are the more or less unfavourable gene
combinations. Each living species or race may be
thought of as occupying one of the available peaks in the
field of gene combinations» (Dobzhansky 1937 p. 187; cf.
Wright 1932 p. 356, Eldredge 1985 p. 27).
10

11. Dobzhansky’s adaptive landscape (1937)
• «In an organism possessing only 1000 genes each
capable of producing ten allelomorphs, the number of the
possible gene combinations that may be formed is 101000.
Some, probably a great majority, of these combinations
are discordand and have no survival value, but still very
numerous ones may be supposed to be harmonious in
the different ecological niches of the same environment,
as well as in different environments. If the entire ideal
field of possible gene combinations is graded with
respect to adaptive value, we may find numerous
“adaptive peaks” separated by “valleys”. The “peaks” are
fitness
the groups of related gene combinations that make their
carriers fit for survival in a given environment; the
“valleys” are the more or less unfavourable gene
combinations. Each living species or race may be thought
of as occupying one of the available peaks in the field of
gene combinations» (Dobzhansky 1937 p. 187; cf. Wright
1932 p. 356, Eldredge 1985 p. 27).
11

12. Dobzhansky’s adaptive landscape (1937)
• «In an organism possessing only 1000 genes each
capable of producing ten allelomorphs, the number of the
possible gene combinations that may be formed is 101000.
Some, probably a great majority, of these combinations
are discordand and have no survival value, but still very
numerous ones may be supposed to be harmonious in
the different ecological niches of the same environment,
as well as in different environments. If the entire ideal
field of possible gene combinations is graded with
respect to adaptive value, we may find numerous
“adaptive peaks” separated by “valleys”. The “peaks” are
the groups of related gene combinations that make their
carriers fit for survival in a given environment; the
“valleys” are the more or less unfavourable gene metaphor
combinations. Each living species or race may be thought
of as occupying one of the available peaks in the field of
gene combinations» (Dobzhansky 1937 p. 187; cf. Wright
1932 p. 356, Eldredge 1985 p. 27).
12

13. Dobzhansky’s adaptive landscape (1937)
• «In an organism possessing only 1000 genes each
capable of producing ten allelomorphs, the number of
the possible gene combinations that may be formed is
101000. Some, probably a great majority, of these
combinations are discordand and have no survival value,
but still very numerous ones may be supposed to be
harmonious in the different ecological niches of the same
environment, as well as in different environments. If the
entire ideal field of possible gene combinations is graded
with respect to adaptive value, we may find numerous
“adaptive peaks” separated by “valleys”. The “peaks”
are the groups of related gene combinations that make
their carriers fit for survival in a given environment; the
“valleys” are the more or less unfavourable gene
combinations. Each living species or race may be
thought of as occupying one of the available peaks in the
field of gene combinations» (Dobzhansky 1937 p. 187; cf.
relatedness
Wright 1932 p. 356, Eldredge 1985 p. 27).
13

14. Dobzhansky’s adaptive landscape (1937)
• «In an organism possessing only 1000 genes each
capable of producing ten allelomorphs, the number of
the possible gene combinations that may be formed is
101000. Some, probably a great majority, of these
combinations are discordand and have no survival value, genetic map
but still very numerous ones may be supposed to be
harmonious in the different ecological niches of the same
environment, as well as in different environments. If the
entire ideal field of possible gene combinations is graded
with respect to adaptive value, we may find numerous fitness
“adaptive peaks” separated by “valleys”. The “peaks” are
the groups of related gene combinations that make their
carriers fit for survival in a given environment; the
“valleys” are the more or less unfavourable gene metaphor
combinations. Each living species or race may be thought
of as occupying one of the available peaks in the field of
relatedness
gene combinations» (Dobzhansky 1937 p. 187; cf. Wright
1932 p. 356, Eldredge 1985 p. 27).
14

15. Dobzhansky’s adaptive landscape (1937)
• «...species tend to be subdivided into numerous isolated colonies
of different size, with the exchange of individuals between the
colonies prevented [...] such a situation is by no means imaginary;
on the contrary, it is very frequently encountered in nature» (e.g.,
p. 133; cf. Wright 1932, Eldredge 1985 p. 21).
• Above the species level:
• «...the adaptive peaks and valleys are not interspersed at random.
“Adjacent” adaptive peaks are arranged in groups, which may be
likened to mountain ranges in which the separate pinnacles are
divided by relatively shallow notches. Thus, the ecological niche
occupied by the species “lion” is relatively much closer to those
occupied by tiger, puma, and leopard than to those occupied by
wolf, coyote, and jackal. The feline adaptive peaks form a group
different from the group of the canine “peaks.” But the feline,
canine, ursine, musteline, and certain other groups of peaks form
together the adaptive “range” of carnivores, which is separated
by deep adaptive valleys from the “ranges” of rodents, bats,
ungulates, primates, and others» (1951, p. 10).
15

16. Dobzhansky’s adaptive landscape (1937)
• «...species tend to be subdivided into numerous isolated colonies
of different size, with the exchange of individuals between the
genetic map???
colonies prevented [...] such a situation is by no means imaginary;
on the contrary, it is very frequently encountered in nature» (e.g.,
p. 133; cf. Wright 1932, Eldredge 1985 p. 21).
• Above the species level:
• «...the adaptive peaks and valleys are not interspersed at random.
“Adjacent” adaptive peaks are arranged in groups, which may be
likened to mountain ranges in which the separate pinnacles are
divided by relatively shallow notches. Thus, the ecological niche
occupied by the species “lion” is relatively much closer to those
occupied by tiger, puma, and leopard than to those occupied by
wolf, coyote, and jackal. The feline adaptive peaks form a group
different from the group of the canine “peaks.” But the feline,
canine, ursine, musteline, and certain other groups of peaks form
together the adaptive “range” of carnivores, which is separated
by deep adaptive valleys from the “ranges” of rodents, bats,
ungulates, primates, and others» (1951, p. 10).
16

17. Dobzhansky’s adaptive landscape (1937)
• «...species tend to be subdivided into numerous isolated colonies
of different size, with the exchange of individuals between the
genetic map???
colonies prevented [...] such a situation is by no means imaginary;
on the contrary, it is very frequently encountered in nature» (e.g.,
p. 133; cf. Wright 1932, Eldredge 1985 p. 21).
• Above the species level:
• «...the adaptive peaks and valleys are not interspersed at random.
“Adjacent” adaptive peaks are arranged in groups, which may be
likened to mountain ranges in which the separate pinnacles are
divided by relatively shallow notches. Thus, the ecological niche
occupied by the species “lion” is relatively much closer to those
occupied by tiger, puma, and leopard than to those occupied by
wolf, coyote, and jackal. The feline adaptive peaks form a group
different from the group of the canine “peaks.” But the feline, niche???
canine, ursine, musteline, and certain other groups of peaks form
together the adaptive “range” of carnivores, which is separated
by deep adaptive valleys from the “ranges” of rodents, bats,
ungulates, primates, and others» (1951, p. 10).
17

18. Dobzhansky’s adaptive landscape (1937)
• «In an organism possessing only 1000 genes each
capable of producing ten allelomorphs, the number of the
possible gene combinations that may be formed is 101000.
Some, probably a great majority, of these combinations
are discordand and have no survival value, but still very
numerous ones may be supposed to be harmonious in
the different ecological niches of the same
environment, as well as in different environments. If the
entire ideal field of possible gene combinations is graded
with respect to adaptive value, we may find numerous
“adaptive peaks” separated by “valleys”. The “peaks” are
the groups of related gene combinations that make their niche
carriers fit for survival in a given environment; the
“valleys” are the more or less unfavourable gene
combinations. Each living species or race may be
thought of as occupying one of the available peaks in
the field of gene combinations» (Dobzhansky 1937 p.
187; cf. Wright 1932 p. 356, Eldredge 1985 p. 27).
18

19. Niches and landscapes
(environment)
• ...in the different ecological niches
of the same environment, as well as
in different environments...
• ...the ecological niche occupied by
the species “lion” is relatively much
closer to those occupied by tiger...
19

20. Niches and landscapes
(environment)
• ...in the different ecological niches
of the same environment, as well as
in different environments... ???
• ...the ecological niche occupied by
the species “lion” is relatively much
closer to those occupied by
tiger... ???
20

21. Niches and landscapes
(environment)
21

22. Niches and landscapes
(environment)
We have been (or, for some reasons, we are) brought to identify, to conflate a
discrete and scattered distibution in the genotypic space (i.e., the space of
possible genotypic combinations) and a discrete array of different sets of
selective pressures.
22

23. Speciation and landscapes
Dobzhansky, Modern Synthesis
1) environmental changes make
Sewall Wright populations move geographically
(1932)
2) geographical isolation can happen
3) geographical isolation is evolutionarily
important because it can eventually bring
to genetic isolation (hybrid unviability or
sterility)
4) moving in a new environment can
result in novel adaptations 23

24. Speciation, adaptation, and landscapes
Geographic speciation,
geographic adaptation...
24

25. THREE COORDINATING SPACES
25

26. Criticizing adaptive landscapes and the conflation
between ecology and genealogy
• There are habits of thinking evolution that have to do with conflating
ecology and genealogy, and they can lead to inconsistencies in our
thoughts.
• Dobzhansky’s (1937) famous version of the adaptive landscape is a
good instance of this conflation.
• Its influence may constrain our though in perpetuating these
conflations.
• I see three coordinated spaces (genotypic, geographical, selective
pressures) conflated in the landscape.
• To avoid inconsistencies, geographic and genealogical groups
should be grouped on different hierarchies (disentanglement).
• OPEN ENDED ON HIERARCHY THEORY:
• Where selective pressures (not a proper space)?
26

27. Criticizing adaptive landscapes and the conflation
between ecology and genealogy
Emanuele Serrelli
University of Milano Bicocca, Italy
27