Pleiotropic jaw morphology links the evolution of mechanical modularity and functional feeding convergence in Lake Malawi cichlids

Complexity in how mechanistic variation translates into ecological novelty could be critical to organismal diversification. For instance, when multiple distinct morphologies can generate the same mechanical or functional phenotype, this could mitigate trade-offs and/or provide alternative ways to meet the same ecological challenge. To investigate how this type of complexity shapes diversity in a classic adaptive radiation, we tested several evolutionary consequences of the anterior jaw four-bar linkage for Lake Malawi cichlid trophic diversification. Using a novel phylogenetic framework, we demonstrated that different mechanical outputs of the same four jaw elements are evolutionarily associated with both jaw protrusion distance and jaw protrusion angle. However, these two functional aspects of jaw protrusion have evolved independently. Additionally, although four-bar morphology showed little evidence for attraction to optima, there was substantial evidence of adaptive peaks for emergent four-bar linkage mechanics and jaw protrusion abilities among Malawi feeding guilds. Finally, we highlighted a clear case of two cichlid species that have independently evolved to graze algae in less than 2 Myr and have converged on similar jaw protrusion abilities as well as four-bar linkage mechanics, but have evolved these similarities via non-convergent four-bar morphologies.

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New Three-Spotted Cichlid Species with Hypertrophied Lips (Teleostei: Cichlidae) from the Deep Waters of Lake Malaŵi/Nyasa, Africa

Copeia ◽

10.1643/0045-8511(2001)001[0705:ntscsw]2.0.co;2 ◽

2001 ◽

Vol 2001 (3) ◽

pp. 705-717 ◽

Cited By ~ 12

Author(s):

Matthew E. Arnegard ◽

Jos Snoeks

Keyword(s):

Lake Malawi ◽

Cichlid Species ◽

Deep Waters

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Interspecific hybridization can generate functional novelty in cichlid fish

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.1621 ◽

2019 ◽

Vol 286 (1913) ◽

pp. 20191621 ◽

Cited By ~ 6

Author(s):

O. M. Selz ◽

O. Seehausen

Keyword(s):

Interspecific Hybridization ◽

First Generation ◽

Parental Species ◽

Cichlid Fish ◽

Context Dependency ◽

Functional Variation ◽

Generate Functional ◽

Cichlid Species ◽

Evolutionary Consequences ◽

African Cichlids

The role of interspecific hybridization in evolution is still being debated. Interspecific hybridization has been suggested to facilitate the evolution of ecological novelty, and hence the invasion of new niches and adaptive radiation when ecological opportunity is present beyond the parental species niches. On the other hand, hybrids between two ecologically divergent species may perform less well than parental species in their respective niches because hybrids would be intermediate in performance in both niches. The evolutionary consequences of hybridization may hence be context-dependent, depending on whether ecological opportunities, beyond those of the parental species, do or do not exist. Surprisingly, these complementary predictions may never have been tested in the same experiment in animals. To do so, we investigate if hybrids between ecologically distinct cichlid species perform less well than the parental species when feeding on food either parent is adapted to, and if the same hybrids perform better than their parents when feeding on food none of the species are adapted to. We generated two first-generation hybrid crosses between species of African cichlids. In feeding efficiency experiments we measured the performance of hybrids and parental species on food types representing both parental species niches and additional ‘novel’ niches, not used by either of the parental species but by other species in the African cichlid radiations. We found that hybrids can have higher feeding efficiencies on the ‘novel’ food types but typically have lower efficiencies on parental food types when compared to parental species. This suggests that hybridization can generate functional variation that can be of ecological relevance allowing the access to resources outside of either parental species niche. Hence, we provide support for the hypothesis of ecological context-dependency of the evolutionary impact of interspecific hybridization.

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Epidemiological and evolutionary consequences of life‐history trade‐offs in pathogens

Plant Pathology ◽

10.1111/ppa.12129 ◽

2013 ◽

Vol 62 (S1) ◽

pp. 96-105 ◽

Cited By ~ 37

Author(s):

A.‐L. Laine ◽

B. Barrès

Keyword(s):

Life History ◽

Trade Offs ◽

Evolutionary Consequences

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Species differences in courtship acoustic signals among five Lake Malawi cichlid species (Pseudotropheus spp.)

Journal of Fish Biology ◽

10.1111/j.1095-8649.2008.01802.x ◽

2008 ◽

Vol 72 (6) ◽

pp. 1355-1368 ◽

Cited By ~ 64

Author(s):

M. C. P. Amorim ◽

J. M. Simões ◽

P. J. Fonseca ◽

G. F. Turner

Keyword(s):

Species Differences ◽

Acoustic Signals ◽

Lake Malawi ◽

Cichlid Species

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Are some individuals generally more behaviorally plastic than others? An experiment with sailfin mollies

PeerJ ◽

10.7717/peerj.5454 ◽

2018 ◽

Vol 6 ◽

pp. e5454 ◽

Cited By ~ 4

Author(s):

Julie Gibelli ◽

Nadia Aubin-Horth ◽

Frédérique Dubois

Keyword(s):

Individual Differences ◽

Behavioral Plasticity ◽

Behavioral Responses ◽

Learning Task ◽

Behavioral Traits ◽

Physiological Constraints ◽

Trade Offs ◽

Proximate Factors ◽

Evolutionary Consequences ◽

Sailfin Mollies

Individuals within the same population generally differ among each other not only in their behavioral traits but also in their level of behavioral plasticity (i.e., in their propensity to modify their behavior in response to changing conditions). If the proximate factors underlying individual differences in behavioral plasticity were the same for any measure of plasticity, as commonly assumed, one would expect plasticity to be repeatable across behaviors and contexts. However, this assumption remains largely untested. Here, we conducted an experiment with sailfin mollies (Poecilia latipinna) whose behavioral plasticity was estimated both as the change in their personality traits or mating behavior across a social gradient and using their performance on a reversal-learning task. We found that the correlations between pairwise measures of plasticity were weak and non-significant, thus indicating that the most plastic individuals were not the same in all the tests. This finding might arise because either individuals adjust the magnitude of their behavioral responses depending on the benefits of plasticity, and/or individuals expressing high behavioral plasticity in one context are limited by neural and/or physiological constraints in the amount of plasticity they can express in other contexts. Because the repeatability of behavioral plasticity may have important evolutionary consequences, additional studies are needed to assess the importance of trade-offs between conflicting selection pressures on the maintenance of intra-individual variation in behavioral plasticity.

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Broadscale evolutionary analysis of eukaryotic DDE transposons

10.1101/2021.09.26.461848 ◽

2021 ◽

Author(s):

Mathilde Dupeyron ◽

Tobias Baril ◽

Alex Hayward

Keyword(s):

Horizontal Transfer ◽

Evolutionary Analysis ◽

Eukaryotic Evolution ◽

Evolutionary Patterns ◽

Selfish Genetic Elements ◽

Trade Offs ◽

Phylogenetic Framework ◽

Basic Biology ◽

Host Relationships ◽

Animal Hosts

DDE transposons are widespread selfish genetic elements, often comprising a large proportion of eukaryotic genomic content. DDE transposons have also made important contributions to varied host functions during eukaryotic evolution, and their transposases may be the most abundant and ubiquitous genes in nature. Yet much remains unknown about their basic biology. We employ a broadscale screen of DDE transposase diversity to characterise major evolutionary patterns for all 19 DDE transposon superfamilies. We identify considerable variation in DDE transposon superfamily size, and find a dominant association with animal hosts. While few DDE transposon superfamilies specialise in plants or fungi, the four largest superfamilies contain major plant-associated clades, at least partially underlying their relative success. We recover a pattern of host conservation among DDE transposon lineages, punctuated by occasional horizontal transfer to distantly related hosts. Host range and horizontal transfer are strongly positively correlated with DDE transposon superfamily size, arguing against variation in the capacity for generalism. We find that rates of horizontal transfer decrease sharply with increasing levels of host taxonomy, supporting the existence of host-associated barriers to DDE transposon spread. Overall, despite their relatively simple genetic structure, our results imply that trade-offs in host adaptation are important in defining DDE transposon-host relationships and evolution. In addition, our study provides a phylogenetic framework to facilitate the identification and further analysis of DDE transposons.

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Behavioral, morphological, and ecological trait evolution in two clades of New World Sparrows (Aimophila and Peucaea, Passerellidae)

PeerJ ◽

10.7717/peerj.9249 ◽

2020 ◽

Vol 8 ◽

pp. e9249

Author(s):

Carla Cicero ◽

Nicholas A. Mason ◽

Lauryn Benedict ◽

James D. Rising

Keyword(s):

New World ◽

Phylogenetic Signal ◽

Habitat Type ◽

Trait Evolution ◽

Behavioral Traits ◽

Trade Offs ◽

Complex Song ◽

Phylogenetic Framework ◽

Ancestral States ◽

Vocal Duets

The New World sparrows (Passerellidae) are a large, diverse group of songbirds that vary in morphology, behavior, and ecology. Thus, they are excellent for studying trait evolution in a phylogenetic framework. We examined lability versus conservatism in morphological and behavioral traits in two related clades of sparrows (Aimophila, Peucaea), and assessed whether habitat has played an important role in trait evolution. We first inferred a multi-locus phylogeny which we used to reconstruct ancestral states, and then quantified phylogenetic signal among morphological and behavioral traits in these clades and in New World sparrows more broadly. Behavioral traits have a stronger phylogenetic signal than morphological traits. Specifically, vocal duets and song structure are the most highly conserved traits, and nesting behavior appears to be maintained within clades. Furthermore, we found a strong correlation between open habitat and unpatterned plumage, complex song, and ground nesting. However, even within lineages that share the same habitat type, species vary in nesting, plumage pattern, song complexity, and duetting. Our findings highlight trade-offs between behavior, morphology, and ecology in sparrow diversification.

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Longevity and ageing: appraising the evolutionary consequences of growing old

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2005.1738 ◽

2005 ◽

Vol 361 (1465) ◽

pp. 119-135 ◽

Cited By ~ 40

Author(s):

Michael B Bonsall

Keyword(s):

Life History ◽

Biological Diversity ◽

Species Coexistence ◽

Life History Strategies ◽

Life History Trait ◽

Future Research ◽

Ecological Processes ◽

Physiological Processes ◽

Trade Offs ◽

Evolutionary Consequences

Senescence or ageing is an increase in mortality and/or decline in fertility with increasing age. Evolutionary theories predict that ageing or longevity evolves in response to patterns of extrinsic mortality or intrinsic damage. If ageing is viewed as the outcome of the processes of behaviour, growth and reproduction then it should be possible to predict mortality rate. Recent developments have shown that it is now possible to integrate these ecological and physiological processes and predict the shape of mortality trajectories. By drawing on the key exciting developments in the cellular, physiological and ecological process of longevity the evolutionary consequences of ageing are reviewed. In presenting these ideas an evolutionary demographic framework is used to argue how trade-offs in life-history strategies are important in the maintenance of variation in longevity within and between species. Evolutionary processes associated with longevity have an important role in explaining levels of biological diversity and speciation. In particular, the effects of life-history trait trade-offs in maintaining and promoting species diversity are explored. Such trade-offs can alleviate the effects of intense competition between species and promote species coexistence and diversification. These results have important implications for understanding a number of core ecological processes such as how species are divided among niches, how closely related species co-occur and the rules by which species assemble into food-webs. Theoretical work reveals that the proximate physiological processes are as important as the ecological factors in explaining the variation in the evolution of longevity. Possible future research challenges integrating work on the evolution and mechanisms of growing old are briefly discussed.

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