Authors:
Graziela S. Araújo
1
;
Guilherme P. Telles
2
;
Maria Emília M. T. Walter
3
and
Nalvo F. Almeida
1
Affiliations:
1
Federal University of Mato Grosso do Sul, Brazil
;
2
University of Campinas, Brazil
;
3
University of Brasília, Brazil
Keyword(s):
Evolution, Phylogeny, Live Phylogeny, Neighbor-joining.
Abstract:
The Distance-Based Live Phylogeny Problem generalizes the well-known Distance-Based Phylogeny Problem
by admitting live ancestors among the taxonomic objects. This problem suites in cases of fast-evolving species
that co-exist and are ancestors/descendants at the same time, like viruses, and non-biological objects like documents,
images and database records. For n objects, the input is an nn-matrix where position i; j represents
the evolutionary distance between the objects i; j. Output is an unrooted, weighted tree where the objects may
be represented either as leaves or as internal nodes, and the distances between pairs of objects in the tree are
equal to the distances in the corresponding positions in the matrix. When the matrix is additive, it is easy
to find such a tree. In this work we prove that the problem of minimizing the residual differences between
path-lengths along the tree and pairwise distances in the matrix is computationally hard when the matrix is
not additive. We
propose a heuristic, called Live-NJ, to solve the problem that reconstructs the evolutionary
history based on the well-known Neighbor-Joining algorithm. Results shown that Live-NJ performs better
when compared to NJ, being a promising approach to solve the Distance-Based Live Phylogeny Problem.
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