title: Ancestral reconstruction of tick lineages.
abstract: Ancestral reconstruction in its fullest sense aims to describe the complete evolutionary history of a lineage. This depends on accurate phylogenies and an understanding of the key characters of each parental lineage. An attempt is made to delineate our current knowledge with regard to the ancestral reconstruction of the tick (Ixodida) lineage. Tick characters may be assigned to Core of Life, Lineages of Life or Edges of Life phenomena depending on how far back these characters may be assigned in the evolutionary Tree of Life. These include housekeeping genes, sub-cellular systems, heme processing (Core of Life), development, moulting, appendages, nervous and organ systems, homeostasis, respiration (Lineages of Life), specific adaptations to a blood-feeding lifestyle, including the complexities of salivary gland secretions and tick-host interactions (Edges of Life). The phylogenetic relationships of lineages, their origins and importance in ancestral reconstruction are discussed. Uncertainties with respect to systematic relationships, ancestral reconstruction and the challenges faced in comparative transcriptomics (next-generation sequencing approaches) are highlighted. While almost 150 years of information regarding tick biology have been assembled, progress in recent years indicates that we are in the infancy of understanding tick evolution. Even so, broad reconstructions can be made with relation to biological features associated with various lineages. Conservation of characters shared with sister and parent lineages are evident, but appreciable differences are present in the tick lineage indicating modification with descent, as expected for Darwinian evolutionary theory. Many of these differences can be related to the hematophagous lifestyle of ticks.
authors: Parasites, Vectors and Vector-Borne Diseases, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa; Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa; Department of Life and Consumer Sciences, University of South Africa, South Africa. Electronic address: mansb@arc.agric.za.
authors: Ben J
authors: BJ
authors: Mans
authors: Parasites, Vectors and Vector-Borne Diseases, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa; The Biotechnology Platform, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa; Department of Life and Consumer Sciences, University of South Africa, South Africa.
authors: Minique H
authors: MH
authors: de Castro
authors: Parasites, Vectors and Vector-Borne Diseases, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa.
authors: Ronel
authors: R
authors: Pienaar
authors: Parasites, Vectors and Vector-Borne Diseases, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa.
authors: Daniel
authors: D
authors: de Klerk
authors: Parasites, Vectors and Vector-Borne Diseases, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa; Department of Life and Consumer Sciences, University of South Africa, South Africa.
authors: Philasande
authors: P
authors: Gaven
authors: Parasites, Vectors and Vector-Borne Diseases, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa; Department of Life and Consumer Sciences, University of South Africa, South Africa.
authors: Siyamcela
authors: S
authors: Genu
authors: Parasites, Vectors and Vector-Borne Diseases, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa; School of Life Sciences, University of Kwa-Zulu Natal, Durban, South Africa.
authors: Abdalla A
authors: AA
authors: Latif
mesh_terms: D000818:Animals; D005075:Biological Evolution; D026863:Ixodidae / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics* / Q000502:physiology
keywords: Blood-feeding; Evolution; Genomics; Molecular systematics; Next-generation sequencing; Phylogenetics