Phylogeny of the Lake Tanganyika Cichlid Species Flock and Its Relationship to the Central and East African Haplochromine Cichlid Fish Faunas

The species flocks of cichlid fishes in the East African Great Lakes are the largest vertebrate adaptive radiations in the world and illustrious textbook examples of convergent evolution between independent species assemblages. Although recent studies suggest some degrees of genetic exchange between riverine taxa and the lake faunas, not a single cichlid species is known from Lakes Tanganyika, Malawi and Victoria that is derived from the radiation associated with another of these lakes. Here, we report the discovery of a haplochromine cichlid species in Lake Tanganyika, which belongs genetically to the species flock of haplochromines of the Lake Victoria region. The new species colonized Lake Tanganyika only recently, suggesting that faunal exchange across watersheds and, hence, between isolated ichthyofaunas, is more common than previously thought.

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Female preference for conspecific males based on olfactory cues in a Lake Malawi cichlid fish

Biology Letters ◽

10.1098/rsbl.2005.0355 ◽

2005 ◽

Vol 1 (4) ◽

pp. 411-414 ◽

Cited By ~ 97

Author(s):

Martin Plenderleith ◽

Cock van Oosterhout ◽

Rosanna L Robinson ◽

George F Turner

Keyword(s):

Cichlid Fish ◽

Mate Recognition ◽

Lake Malawi ◽

Olfactory Cues ◽

Species Flock ◽

East African ◽

Significant Preference ◽

African Species ◽

Cichlid Species

Research on reproductive isolation in African cichlid fishes has largely focused on the role of nuptial colours, but other sensory modes may play an important role in mate choice. Here, we compare the relative importance of visual and olfactory cues in mate recognition by females of a Lake Malawi cichlid species. Female Pseudotropheus emmiltos were given a choice of spawning next to a conspecific male or a male of the closely-related sympatric Pseudotropheus fainzilberi . Significant preference for conspecific males only occurred when olfactory cues were present. This suggests that divergence of olfactory signals may have been an important influence on the explosive radiation of the East African species flock.

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The Adaptive Radiation of Cichlid Fish in Lake Tanganyika: A Morphological Perspective

International Journal of Evolutionary Biology ◽

10.4061/2011/620754 ◽

2011 ◽

Vol 2011 ◽

pp. 1-14 ◽

Cited By ~ 36

Author(s):

Tetsumi Takahashi ◽

Stephan Koblmüller

Keyword(s):

East Africa ◽

Adaptive Radiation ◽

Lake Tanganyika ◽

Cichlid Fish ◽

Ancient Lakes ◽

Species Assemblage ◽

Cichlid Species ◽

Morphological Studies ◽

Rapid Speciation ◽

Explosive Speciation

Lake Tanganyika is the oldest of the Great Ancient Lakes in the East Africa. This lake harbours about 250 species of cichlid fish, which are highly diverse in terms of morphology, behaviour, and ecology. Lake Tanganyika's cichlid diversity has evolved through explosive speciation and is treated as a textbook example of adaptive radiation, the rapid differentiation of a single ancestor into an array of species that differ in traits used to exploit their environments and resources. To elucidate the processes and mechanisms underlying the rapid speciation and adaptive radiation of Lake Tanganyika's cichlid species assemblage it is important to integrate evidence from several lines of research. Great efforts have been, are, and certainly will be taken to solve the mystery of how so many cichlid species evolved in so little time. In the present review, we summarize morphological studies that relate to the adaptive radiation of Lake Tanganyika's cichlids and highlight their importance for understanding the process of adaptive radiation.

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Differential attack by a cichlid fish on resident and non-resident fish of another cichlid species

Behaviour ◽

10.1163/156853912x629139 ◽

2012 ◽

Vol 149 (1) ◽

pp. 99-109 ◽

Cited By ~ 5

Author(s):

Satoshi Awata ◽

Masanori Kohda ◽

Haruki Ochi

Keyword(s):

Field Experiment ◽

Lake Tanganyika ◽

Cichlid Fish ◽

Previous Experience ◽

Alternative Mechanism ◽

Differential Attack ◽

Dear Enemy ◽

Resident Fish ◽

Cichlid Species ◽

Dear Enemy Effect

AbstractAn algivorous cichlid, Variabilichromis moorii( Vm), defends permanent territories in Lake Tanganyika, Africa. A zoobenthivorous cichlid, Neolamprologus mustax( Nm), spends 60% of daylight hours foraging in Vmterritories, from which other zoobenthivorous fishes are chased out and consequently which are much richer in prey animals than areas outside of Vmterritories. We conducted a field experiment to examine whether Nmresidents and non-residents received different degrees of attacks from Vm. Nmfish were caught in their territories, released at a point distant from these territories, and followed to observe interactions with Vmfish. The frequency of attacks received by the displaced Nmfish was greater than attacks received by Nmresidents, indicating that Nmresidents had easier access to Vmterritories than non-residents did. A possible mechanism for this is reduced aggression of Vmtowards Nmresidents, as a result of the ‘dear enemy’ effect that has been reported in territorial contests between rivals. An alternative mechanism is that tolerance towards Nmdiffers among Vmfish and Nmresidents selectively visit more tolerant Vmfish due to previous experience while non-residents randomly approach both tolerant and hostile Vmfish. The ability of Vmto discriminate between Nmresidents and non-residents is essential to the former mechanism but not to the latter. To more specifically examine which mechanism works in the Vm– Nmcommensal system, we will need to follow individually identified Vmfish interacting with Nmresidents and non-residents.

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A complex mode of aggressive mimicry in a scale-eating cichlid fish

Biology Letters ◽

10.1098/rsbl.2015.0521 ◽

2015 ◽

Vol 11 (9) ◽

pp. 20150521 ◽

Cited By ~ 11

Author(s):

Nicolas Boileau ◽

Fabio Cortesi ◽

Bernd Egger ◽

Moritz Muschick ◽

Adrian Indermaur ◽

...

Keyword(s):

Fish Species ◽

Related Species ◽

Lake Tanganyika ◽

Cichlid Fish ◽

Targeted Sequencing ◽

Complex Mode ◽

Cichlid Species ◽

Aggressive Mimicry ◽

Complex Interactions

Aggressive mimicry is an adaptive tactic of parasitic or predatory species that closely resemble inoffensive models in order to increase fitness via predatory gains. Although similarity of distantly related species is often intuitively implicated with mimicry, the exact mechanisms and evolutionary causes remain elusive in many cases. Here, we report a complex aggressive mimicry strategy in Plecodus straeleni , a scale-eating cichlid fish from Lake Tanganyika, which imitates two other cichlid species. Employing targeted sequencing on ingested scales, we show that P. straeleni does not preferentially parasitize its models but—contrary to prevailing assumptions—targets a variety of co-occurring dissimilar looking fish species . Combined with tests for visual resemblance and visual modelling from a prey perspective, our results suggest that complex interactions among different cichlid species are involved in this mimicry system.

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On the origin of the Synodontis catfish species flock from Lake Tanganyika

Biology Letters ◽

10.1098/rsbl.2006.0532 ◽

2006 ◽

Vol 2 (4) ◽

pp. 548-552 ◽

Cited By ~ 26

Author(s):

Julia J Day ◽

Mark Wilkinson

Keyword(s):

Lake Tanganyika ◽

Sequence Data ◽

Phylogenetic Study ◽

Species Flock ◽

East African ◽

Extrinsic Factors ◽

Factors Affecting ◽

Fossil Calibration ◽

Mtdna Sequence ◽

Species Flocks

Species flocks within Great Lakes provide unique insights into the factors affecting diversification. Lake Tanganyika (LT) is of particular interest because it contains many endemic groups for which general factors affecting diversification can be discerned. Here, we present the first phylogenetic study of the LT Synodontis (Siluriformes, Mochokidae) species flock using mtDNA sequence data. Our data reveal some previously unrecognized species diversity and indicate that the LT species flock is not monophyletic, and that two closely related clades of endemics may have independently colonized LT. Other comparable small species flocks are characterized by a single colonization event. Molecular date estimates of the timing of the initial within-lake diversification of the LT endemics, based on a fossil calibration, are comparable to those reported for other groups, suggesting that extrinsic factors maybe important common causes of clade diversification. The basal divergence in the sampled Synodontis reveals an East–West African faunal split seen in many terrestrial, but few aquatic groups, the timing of which coincides with East African rifting events.

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Description of five new rheophilic Orthochromis species (Teleostei: Cichlidae) from the Upper Congo drainage in Zambia and the Democratic Republic of the Congo

Zootaxa ◽

10.11646/zootaxa.4464.3.1 ◽

2018 ◽

Vol 4461 (3) ◽

pp. 301 ◽

Cited By ~ 5

Author(s):

FREDERIC DIETER BENEDIKT SCHEDEL ◽

EMMANUEL J.W.M.N. VREVEN ◽

BAUCHET KATEMO MANDA ◽

EMMANUEL ABWE ◽

BAUCHET KATEMO MANDA ◽

...

Keyword(s):

New Species ◽

Lake Tanganyika ◽

Democratic Republic ◽

Valid Species ◽

Cichlid Species ◽

Haplochromine Cichlid ◽

Republic Of The Congo

Five new rheophilic haplochromine cichlid species are described from the Upper Congo drainage of Zambia and the Democratic Republic of the Congo: Orthochromis mporokoso sp. nov. and O. katumbii sp. nov. from the Bangwelu-Mweru ecoregion, O. kimpala sp. nov. and O. gecki sp. nov. from the Upper Lualaba ecoregion, and O. indermauri sp. nov. from the Lufubu River of the Lake Tanganyika ecoregion. Orthochromis kimpala sp. nov, O. gecki sp. nov., and O. indermauri sp. nov. are distinguished from all currently valid species of the genus Orthochromis Greenwood 1954, except for O. torrenticola (Thys van den Audenaerde 1963), by the presence of eggspots or eggspot-like maculae on the anal fin (vs. no eggspots). The three species can be easily distinguished from O. torrenticola by having three anal spines (vs. four anal spines). Moreover, all five new species can be individually distinguished from all currently known rheophilic taxa placed in the genera Orthochromis, Schwetzochromis Poll 1948 and the rheophilic species of the genus Haplochromis Hilgendorf 1888 (e.g. H. bakongo Thys van den Audenaerde 1964, H. snoeksi Wamuini Lunkayilako & Vreven 2010, H. vanheusdeni Schedel et al. 2014) either based on meristic values, morphometric distances and colouration patterns, or on a combination of them.

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Ancestral Hybridization Facilitated Species Diversification in the Lake Malawi Cichlid Fish Adaptive Radiation

Molecular Biology and Evolution ◽

10.1093/molbev/msz294 ◽

2019 ◽

Vol 37 (4) ◽

pp. 1100-1113 ◽

Cited By ~ 12

Author(s):

Hannes Svardal ◽

Fu Xiang Quah ◽

Milan Malinsky ◽

Benjamin P Ngatunga ◽

Eric A Miska ◽

...

Keyword(s):

Adaptive Radiation ◽

Large Scale ◽

Lake Victoria ◽

Cichlid Fish ◽

Lake Malawi ◽

Raw Material ◽

Founder Population ◽

East African ◽

Cichlid Species ◽

Show Evidence

Abstract The adaptive radiation of cichlid fishes in East African Lake Malawi encompasses over 500 species that are believed to have evolved within the last 800,000 years from a common founder population. It has been proposed that hybridization between ancestral lineages can provide the genetic raw material to fuel such exceptionally high diversification rates, and evidence for this has recently been presented for the Lake Victoria region cichlid superflock. Here, we report that Lake Malawi cichlid genomes also show evidence of hybridization between two lineages that split 3–4 Ma, today represented by Lake Victoria cichlids and the riverine Astatotilapia sp. “ruaha blue.” The two ancestries in Malawi cichlid genomes are present in large blocks of several kilobases, but there is little variation in this pattern between Malawi cichlid species, suggesting that the large-scale mosaic structure of the genomes was largely established prior to the radiation. Nevertheless, tens of thousands of polymorphic variants apparently derived from the hybridization are interspersed in the genomes. These loci show a striking excess of differentiation across ecological subgroups in the Lake Malawi cichlid assemblage, and parental alleles sort differentially into benthic and pelagic Malawi cichlid lineages, consistent with strong differential selection on these loci during species divergence. Furthermore, these loci are enriched for genes involved in immune response and vision, including opsin genes previously identified as important for speciation. Our results reinforce the role of ancestral hybridization in explosive diversification by demonstrating its significance in one of the largest recent vertebrate adaptive radiations.

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Depth and substratum differentiations among coexisting herbivorous cichlids in Lake Tanganyika

Royal Society Open Science ◽

10.1098/rsos.160229 ◽

2016 ◽

Vol 3 (11) ◽

pp. 160229 ◽

Cited By ~ 2

Author(s):

Hiroki Hata ◽

Haruki Ochi

Keyword(s):

Adaptive Radiation ◽

Rocky Shore ◽

Lake Level ◽

Lake Tanganyika ◽

Cichlid Fish ◽

Species Number ◽

Niche Segregation ◽

Cichlid Species ◽

Feeding Territory ◽

Shed Light

Cichlid fish in Lake Tanganyika represent a system of adaptive radiation in which eight ancestral lineages have diversified into hundreds of species through adaptation to various niches. However, Tanganyikan cichlids have been thought to be oversaturated, that is, the species number exceeds the number of niches and ecologically equivalent and competitively even species coexist. However, recent studies have shed light on niche segregation on a finer scale among apparently equivalent species. We observed depth and substratum preferences of 15 herbivorous cichlids from four ecomorphs (i.e. grazer, browser, scraper and scooper) on a rocky littoral slope for 14 years. Depth differentiation was detected among grazers that defended feeding territories and among browsers with feeding territories. Cichlid species having no feeding territory also showed specificity on depth and substratum, resulting in habitat segregation among species that belong to the same ecomorph. Phylogenetically close species did not occupy adjacent depths, nor the opposite depth zones. Our findings suggest that apparently equivalent species of the same ecomorph coexist parapatrically along depth on a few-metre scale, or coexist with different substratum preferences on the rocky shore, and this niche segregation may have been acquired by competition between encountering equivalent species through repetitive lake-level fluctuations.

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Trophic specialisation reflected by radular tooth material properties in an “ancient” Lake Tanganyikan gastropod species flock

BMC Ecology and Evolution ◽

10.1186/s12862-021-01754-4 ◽

2021 ◽

Vol 21 (1) ◽

Cited By ~ 1

Author(s):

Wencke Krings ◽

Marco T. Neiber ◽

Alexander Kovalev ◽

Stanislav N. Gorb ◽

Matthias Glaubrecht

Keyword(s):

Mechanical Properties ◽

Lake Tanganyika ◽

Ecological Niches ◽

Species Flock ◽

Trophic Specialization ◽

East African ◽

Tooth Morphology ◽

Lake Formation ◽

Feeding Substrate ◽

Radular Tooth

Abstract Background Lake Tanganyika belongs to the East African Great Lakes and is well known for harbouring a high proportion of endemic and morphologically distinct genera, in cichlids but also in paludomid gastropods. With about 50 species these snails form a flock of high interest because of its diversity, the question of its origin and the evolutionary processes that might have resulted in its elevated amount of taxa. While earlier debates centred on these paludomids to be a result of an intralacustrine adaptive radiation, there are strong indications for the existence of several lineages before the lake formation. To evaluate hypotheses on the evolution and radiation the detection of actual adaptations is however crucial. Since the Tanganyikan gastropods show distinct radular tooth morphologies hypotheses about potential trophic specializations are at hand. Results Here, based on a phylogenetic tree of the paludomid species from Lake Tanganyika and adjacent river systems, the mechanical properties of their teeth were evaluated by nanoindentation, a method measuring the hardness and elasticity of a structure, and related with the gastropods’ specific feeding substrate (soft, solid, mixed). Results identify mechanical adaptations in the tooth cusps to the substrate and, with reference to the tooth morphology, assign distinct functions (scratching or gathering) to tooth types. Analysing pure tooth morphology does not consistently reflect ecological specializations, but the mechanical properties allow the determination of eco-morphotypes. Conclusion In almost every lineage we discovered adaptations to different substrates, leading to the hypothesis that one main engine of the flock’s evolution is trophic specialization, establishing distinct ecological niches and allowing the coexistence of taxa.

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