Why grow up? A perspective on insect strategies to avoid metamorphosis

  title={Why grow up? A perspective on insect strategies to avoid metamorphosis},
  author={Dino P. McMahon and Alexander Hayward},
  journal={Ecological Entomology},
1. Insects with complete metamorphosis (holometaboly) are extremely successful, constituting over 60% of all described animal species. Complete metamorphosis confers significant advantages because it enables organisms to optimise life‐history components through temporal partitioning, and thereby to exploit multiple ecological niches. Yet holometaboly can also impose costs, and several lineages have evolved life cycle modifications to avoid complete metamorphosis. 

Complete metamorphosis of insects

It is proposed that the main adaptive benefit of complete metamorphosis is decoupling between growth and differentiation, which facilitates the exploitation of ephemeral resources and enhances the probability of the metamorphic transition escaping developmental size thresholds.

Links between metamorphosis and symbiosis in holometabolous insects

Across disparate insect taxa, microbes protect hosts from pathogen infection, supply nutrients essential for rebuilding the adult body and provide cues regulating pupation and future research will undoubtedly reveal more links between metamorphosis and microbiota, two widespread features of animal life.

Evolution of complex life cycles

The main result of this thesis is that metamorphosis is difficult to evolve, but, once evolved, it is a robust strategy that does not easily disappear.

Robustness of life histories to environmental variability in complex versus simple life cycles

The relative advantage, in terms of long-run growth rate, of CLC over SLC phenotypes for a broad spectrum of life histories is derived, and which life histories that benefit most by a CLC are explored, to avoid correlation in vital rates between life stages.

Life History Traits

It is shown that lower developmental threshold temperature and thermal constant are important factors to determine life history patterns and 50% emergence date, of which the latter is essential to evaluate the degree of synchronization of emergence and host plant phenology.

Life History Evolution in Lampreys: Alternative Migratory and Feeding Types

  • M. DockerI. Potter
  • Environmental Science, Biology
    Lampreys: Biology, Conservation and Control
  • 2019
The existence of three closely related freshwater parasitic species suggests that Pacific lamprey successfully colonized fresh water in the past, and the “invasion-by-canal” hypothesis appears to be the most convincing, but definitive resolution should be possible with genome-level analyses.

The evolution of lamprey (Petromyzontida) life history and the origin of metamorphosis

A review synthesizes findings and concludes that the ancestral lamprey life cycle followed a direct development, suggesting that the larval period was short and relatively limited if present at all, but that the juvenile included modern larval traits.

Metamorphosis shapes cranial diversity and rate of evolution in salamanders

Recon reconstructs the cranial evolution of the salamander using geometric morphometric data from 148 species spanning the order’s full phylogenetic, developmental and ecological diversity to demonstrate that life cycle influences cranial shape diversity and rate of evolution.



The origins of insect metamorphosis

The three stages of the ancestral insect species—pronymph, nymph and adult—are proposed to be equivalent to the larva, pupa and adult stages of insects with complete metamorphosis, which has general implications for insect developmental biology.

A System Favoring the Evolution of Holometabolous Development

A system for evolving holometabolous development from more direct types of metamorphosis is presented, which predicts a fissioning of direct development into distinct components typical of holometaboly.

Host and Symbiont Jointly Control Gut Microbiota during Complete Metamorphosis

This work studies how the host Galleria mellonella and the symbiotic bacterium Enterococcus mundtii interact to manage the composition of the microbiota during metamorphosis, revealing an interaction that guarantees the safe passage of the symbiont through metamorphoses and benefits the resulting adult host.

Developmental plasticity and the evolution of animal complex life cycles

  • A. MinelliG. Fusco
  • Biology, Psychology
    Philosophical Transactions of the Royal Society B: Biological Sciences
  • 2010
It is hypothesized that a diversity of phenotypes arranged in developmental sequence throughout an animal's life cycle may have evolved by genetic assimilation of alternative phenotypes originally triggered by environmental cues.

The pupal specifier broad directs progressive morphogenesis in a direct-developing insect.

The results suggest that metamorphosis in insects arose as expression of br, which conveys competence for change, became restricted to one postembryonic instar, and the progressive changes that occur within the nymphal series in basal insects became compressed to the one short period of morphogenesis seen in the larva-to-pupa transition of holometabolous insects.

The life cycle of Micromalthus debilisLeConte (1878) (Coleoptera: Archostemata: Micromalthidae): historical review and evolutionary perspective

It is speculated that Micromalthus is dependent on maternally transmitted bacteria for the ability to digest rotting wood, and that these bacteria are senescent in males, causing males to be obligately cannibalistic.

Multiple ancient origins of neoteny in Lycidae (Coleoptera): consequences for ecology and macroevolution

A phylogenetic analysis of Lycidae based on DNA sequences from nuclear (18S and 28S rRNA) and mitochondrial (rrnL, cox1, cob and nad5) genes from a representative set of lineages supported three independent origins of neotenic taxa, contradicting earlier suggestions of recent evolution from dispersive non-neotenics.

Paedogenesis in the dipteran insect Heteropeza pygmaea: an interpretation

A comparison of the modified oocyte development in paedogenetic reproduction with ‘regular’ oogenesis in imaginal reproduction of H. pygmaea shows that the paedogenetically developing eggs start

The phylogeny and limits of Elateridae (Insecta, Coleoptera): is there a common tendency of click beetles to soft‐bodiedness and neoteny?

Kundrata, R. & Bocak, L. (2011). The phylogeny and limits of Elateridae (Insecta, Coleoptera): is there a common tendency of click beetles to soft‐bodiedness and neoteny? —Zoologica Scripta, 40,

The role of Broad in the development of Tribolium castaneum: implications for the evolution of the holometabolous insect pupa

The findings show that the br isoforms functions are broadly conserved within the Holometabola and suggest that evolution of br isoform expression may have played an important role in the evolution of the pupa in holometabolous insects.