The Evolutionary Biology of Cave Fishes

Work from the Cave Biology Research Group

Department of Biology

New York University

Under the direction of Richard Borowsky

(This page is always evolving and presents work in progress.)

This page is intended to disseminate information about our laboratory's work on the biology and genetics of cave fishes. The focus on cave fishes stems from long-term research interests in the evolution of complex traits and the phenomenon of regressive evolution.

Two of the fishes we work on are illustrated below: The top photograph shows the Waterfall Climbing Cave Fish of Thailand, Cryptotora ("Homaloptera") thamicola (Photo by Denis Belliveau), a balitorid hillstream loach. The bottom photograph shows the Blind Mexican Tetra, Astyanax mexicanus, a characid related to the pirahna.

These two fishes, from distantly related families, illustrate two obvious convergences of cave adapted species: both are blind and depigmented. The Cave Biology Research Group (CBRG) at New York University is dedicated to discovering the genetic and evolutionary mechanisms for this convergence.

Cryptotora thamicola (Balitoridae)

Astyanax mexicanus (Characidae)

Current research in the laboratory focuses on the cave loaches of South-east Asia and the blind cave tetras of Northeastern Mexico. For both groups of fishes, the approach is multi-level and includes field work and molecular biology. Molecular techniques include DNA sequencing of both mitochondrial and nuclear genes and DNA Fingerprinting using both RAPD and AFLP technology. The molecular data is used to investigate the phylogenetic relationships of the cave species to their nearest surface relatives, to estimate the relationships among cave populations and their effective population sizes, and to estimate their phylogenetic ages as lines distinct from surface relatives.

This page provides links to other pages and images with raw data and reports from the laboratory.

Please address inquiries to Richard Borowsky: rb4@scires.nyu.edu

Molecular Data and the Phylogeny of Fishes:

• About the fish, the data and the trees

• Balitorid river loaches of Thailand

mtDNA sequences (cytoB) and tree

mtDNA sequences (12srRNA) and tree

RAPD data and tree

PAX6 intron sequences

• The Mexican tetra, Astyanax mexicanus

Mitochondrial DNA sequences and tree

RAPD data and trees

PAX6 intron sequences

Reports, Papers, Manuscripts:

• Cave Fishes of South-Western and Peninsular Thailand, March 1998
• Antiquity and Origins of Troglobitic Mexican Tetras, Astyanax fasciatus.
• McFail's Cave Trip Report
• Updated: Eyed Cave Fish in a Karst Window.
• Updated: Schistura oedipus from NW Thailand: molecular variation among cave populations.
• Updated: Nucleotide Diversity from RAPD data. 2001 MPE 18:143-148
• Updated: Nucleotide Diversity in Thai Balitorid Cave Fishes.
• New: Mapping a Cave Fish Genome

Richard Borowsky, Department of Biology, New York University, Washington Square, NY 10003

Voice (212) 998-8260; Fax (212) 995-4015

rb4@scires.nyu.edu

Web page and authored links © 1998, 1999, 2000 Richard Borowsky, Department of Biology, New York University.

No reproduction of content without prior consent of the author.