[13] Surface temperatures generally range from about 24 °C (75 °F) in the southern part of the lake in early August to 28–29 °C (82–84 °F) in the late rainy season in March—April.

[19][20] The oxygen-devoid deepest sections contain high levels of toxic hydrogen sulfide and are essentially lifeless,[6] except for bacteria.

[28] Almost all (roughly 98%) of the lake's cichlid species are found solely there, and nowhere else, thus making it a precious biological resource for the study of speciation and evolution.

[29][30] The cichlids of the African Great Lakes, including Tanganyika, represent the most diverse extent of adaptive radiation in vertebrates.

[9] Likewise, many tropical riverine species would likely suffer if exposed to the crisp, alkaline lake water.

[37] Some of the deepwater genera (e.g., Bathybates, Gnathochromis, Hemibates and Xenochromis) have been caught in places virtually devoid of oxygen, and how they are able to survive there is unclear.

[36][20] Tanganyika cichlids differ extensively in ecology, and include species that are herbivores, detritivores, planktivores, insectivores, molluscivores, scavengers, scale-eaters and piscivores.

That is, many species of Tanganyikan cichlid with specialized diets showed opportunistic, episodic exploitation of Stolothrissa tanganicae and Limnothrissa miodon when prey concentrations were unusually high.

[39] The fishes' breeding behavior falls into two main groups: the substrate- or sand-spawners (often in caves or rock crevices) and the mouthbrooders.

[28][43] Many cichlids from Lake Tanganyika, such as species from the genera Altolamprologus, Cyprichromis, Eretmodus, Julidochromis, Lamprologus, Neolamprologus, Tropheus and Xenotilapia, are popular aquarium fish due to their bright colors and patterns, and interesting behaviors.

[40] Recreating a Lake Tanganyika biotope to host those cichlids in a habitat similar to their natural environment is also popular in the aquarium hobby, with many species today being bred in captivity successfully.

[38] Among the more unusual fish in the lake are the endemic, facultatively brood parasitic "cuckoo catfish", including at least Synodontis grandiops[65] and S.

[19][40] Six catfish genera are entirely restricted to the lake basin: Bathybagrus, Dinotopterus, Lophiobagrus, Phyllonemus, Pseudotanganikallabes and Tanganikallabes.

[53][67] Although not endemic on a genus level, six species of Chrysichthys catfish are only found in the Tanganyika basin where they live both in shallow and relatively deep waters;[53] in the latter habitat they are the primary predators and scavengers.

[20] A unique evolutionary radiation in the lake is the 15 species of Mastacembelus spiny eels, all but one endemic to its basin.

[68] Among the non-endemic fish, some are widespread African species but several are only shared with the Malagarasi and Congo River basins, such as the Congo bichir (Polypterus congicus), goliath tigerfish (Hydrocynus goliath), Citharinus citharus, six-banded distichodus (Distichodus sexfasciatus) and mbu puffer (Tetraodon mbu).

[69] Among the endemic bivalves are three monotypic genera: Grandidieria burtoni, Pseudospatha tanganyicensis and Brazzaea anceyi.

Their appearance is now believed to be the result of the highly diverse habitats in Lake Tanganyika and evolutionary pressure from snail-eating fish and, in particular, Platythelphusa crabs.

[27][70][71] A total of 17 freshwater snail genera are endemic to the lake, such as Hirthia, Lavigeria, Paramelania, Reymondia, Spekia, Stanleya, Tanganyicia and Tiphobia.

[70] There are about 30 species of non-thalassoid snails in the lake, but only five of these are endemic, including Ferrissia tanganyicensis and Neothauma tanganyicense.

[79] Among these, Limnocaridina iridinae lives inside the mantle cavity of the unionid mussel Pleiodon spekei, making it one of only two known commensal species of freshwater shrimp (the other is the sponge-living Caridina spongicola from Lake Towuti, Indonesia).

[86] Lake Tanganyika supports a major fishery, which, depending on source, provides 25–40%[87] or c. 60% of the animal protein in the diet of the people living in the region.

With the aid of the Graf Goetzen, the Germans had complete control of the lake in the early stages of the war.

The ship was used both to ferry cargo and personnel across the lake, and as a base from which to launch surprise attacks on Allied troops.

Under the command of Lieutenant Commander Geoffrey Spicer-Simson the British Royal Navy achieved the monumental task of bringing two armed motor boats HMS Mimi and HMS Toutou from England to the lake by rail, road and river to Albertville (since renamed Kalemie in 1971) on the western shore of Lake Tanganyika.

[93] In order to avoid his prize ship falling into Allied hands, Zimmer scuttled the vessel on July 26, 1916.