background: aquatic ecosystems are frequently subjected to contamination by toxic heavy metals and pesticides, yet very little is known about the influence of pesticides on bioaccumulation of heavy metals in aquatic organisms. mercury is a toxic metal with no known biological benefit to organisms. bioavailability of mercury in aquatic environments depends on biological and non-biological parame...

background: the presence of pesticide due to the huge demand for agricultural purposes is very prevalent in surface waters of iran. these pesticides could finally accumulate in aquatic ecosystems and have been proved to have toxic effects on aquatic animals. the aim of this study was to assess the acute toxicity of diazinon, deltamethrin, butachlor and pretilachlor on zebra cichlid (cryptoheros...

We have found evidence for ultraviolet visual capabilities in a Lake Malawi cichlid fish, Metriaclima zebra. Microspectrophotometry of single cones revealed a visual pigment with peak sensitivity at 368+/-4 nm. M. zebra also expresses a putative ultraviolet opsin gene whose sequence is closely related to the SWS-1 opsin for other fishes. Several other African cichlids have a functional copy of ...

Background: The presence of pesticide due to the huge demand for agricultural purposes is very prevalent in surface waters of Iran. These pesticides could finally accumulate in aquatic ecosystems and have been proved to have toxic effects on aquatic animals. The aim of this study was to assess the acute toxicity of Diazinon, Deltamethrin, Butachlor and Pretilachlor on Zebra Cichlid (Cryptoheros...

the zebra cichlid cichlasoma nigrofasciatum is a species famous for its behaviors of biparental care. this study was conducted to examine the effect of parental care and their size on the reproductive success of this fish. hatching rate (hrs) has significant difference (p

Background: Aquatic ecosystems are frequently subjected to contamination by toxic heavy metals and pesticides, yet very little is known about the influence of pesticides on bioaccumulation of heavy metals in aquatic organisms. Mercury is a toxic metal with no known biological benefit to organisms. Bioavailability of mercury in aquatic environments depends on biological and non-biological parame...

Abstract Female cichlid fish living in African great lakes are known to have sensory systems that adapted ambient light environments. These system adaptations hypothesized influenced the evolution of diverse male nuptial coloration. In rock-dwelling Lake Malawi mbuna cichlids, however, extent which environments influence female and potentially associated coloration remains unknown. Yet, ubiquit...

Courtship sounds made by three sympatric cichlid species, Pseudotropheus zebra, P. callainos and an undescribed species known as P. ‘zebra gold’ were recorded and compared to investigate the potential role of acoustic signals in mate choice. Sounds were emitted during ‘quiver’ and ‘circle’ components of the male courtship display and consisted of rapidly repeated pulse units. Some sound variabl...

African cichlid fishes are an ideal system for studying explosive rates of speciation and the origin of diversity in adaptive radiation. Within the last few million years, more than 2000 species have evolved in the Great Lakes of East Africa, the largest adaptive radiation in vertebrates. These young species show spectacular diversity in their coloration, morphology and behavior. However, littl...