Criticizing adaptive landscapes, ecology and genealogy

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.

Emanuele is also organizer of the “Hierarchy theory” session at the conference.


Look for it in the Publications page (with additional links):

Serrelli E (2011). Criticizing adaptive landscapes and the conflation between ecology and genealogy. Meeting of the International Society for History, Philosophy, and Social Studies of Biology (ISHPSSB), Salt Lake City (Utah, USA), July 10-16. [http://hdl.handle.net/10281/28191]

http://www.slideshare.net/eserrelli/criticizing-adaptive-landscapes-and-the-conflation-between-ecology-and-genealogy

Hierarchy Theory in Salt Lake City

In 2010 Emanuele Serrelli co-organized the session “Hierarchy Theory of Evolution” inviting Niles Eldredge and 10 other scholars on Hierarchy Theory at the International Society for the History, Philosophy, and Social Studies of Biology Sunday, July 10, 2011 ‐ Friday, July 15, 2011, University of Utah Salt Lake City, Utah United States. Hierarchy Theory assumes that the evolutionary disciplines have an ontological basis for their existence, i.e. systems with peculiar spatiotemporal dimensions, origins, histories, demises, and internal dynamics leading to stability and change through time. The theory is developing around Eldredge’s recognition of at least two main distinct evolutionary hierarchies – the genealogical and the ecological – and around a general vision of evolution as a process of interactions at various scales. E.g., macro-evolutionary patterns are explained by a “sloshing bucket” model, where ecological events reverberate in the evolutionary hierarchy.

MORNING SESSION 1:

  • BROOKS, Dan – Metaphors for the Extended Synthesis: Something Old, Something New.
  • CAIANIELLO, Silvia – Modularity and Hierarchy Theory.
  • CAPORAEL, Linnda – Grounding Human Social Cognition in Hierarchical Group Structure.

MORNING SESSION 2:

  • DIETL, Gregory – Toward a Unified Ecology in Macroevolution.
  • ELDREDGE, Niles – A Matter of Individuality: Hierarchy Theory at the Dawn of Evolutionary Biology.
  • MILLER, William – Macroevolutionary Consonance and expansion of the Modern Synthesis.

AFTERNOON SESSION:

See full session abstracts on Academia.