Map indicating Guyana in South America.

Guyana

South America

Fall 2016

In attendance: Ben Sandkam, Felix Breden, Judith Mank, Godfrey Bourne, Fran Breden

The purpose of this trip was to secure high molecular weight DNA from Poecilia parae, Poecilia picta, Poecilia reticulata. We are using 10X Genomics micro droplet based sequencing methods to sequence the genomes of these species.

This expedition has already resulted in one paper in PNAS focusing on Poecilia picta and I am currently using this data to discover how supergenes were formed in Poecilia parae.

Four scientists sort freshly caught fish in a net by species.
Four scientists sort freshly caught fish in a net by species.

Ben using a hand seine net to catch fish in narrow stream.
Ben using a hand seine net to catch fish in narrow stream.

Ben and Felix sorting fish by species outside a house
Ben and Felix sorting fish by species outside a house

Four scientists sort freshly caught fish in a net by species.
Four scientists sort freshly caught fish in a net by species.

Summer 2010

In attendance: Ben Sandkam, Felix Breden, Godfrey Bourne, Fran Breden* (undergraduate)

The purpose of this trip was to study the visual system of Poecilia parae, Poecilia picta, Poecilia reticulata which are three closely related species of freshwater fish that all school together in the shallow streams of coastal Guyana.


We found that visual systems differed more across different populations of the same species, than across species within the same location. While in Guyana we stayed at CEIBA biological station and traveled to many populations.

CEIBA Biological Station
Kiddie pools set up under tarps at the CEIBA Biological Station

Many samples we preserved at the stream but we also brought some live fish back to the field station and kept them in kiddie pools.

Catching fish
Ben catching fish with a dip net in a narrow drainage ditch

The shallow streams of Guyana are home to three species of closely related fishes: Poecilia parae, Poecilia picta and Poecilia reticulata.

Shopping for dinner
Meat for sale at an open air market.

CEIBA Biological Station
Kiddie pools set up under tarps at the CEIBA Biological Station

Many samples we preserved at the stream but we also brought some live fish back to the field station and kept them in kiddie pools.

Map indicating Trinidad and Tobago

Trinidad

South America

Fall 2016

In attendance: Ben Sandkam, Felix Breden, Judith Mank, Godfrey Bourne, Fran Breden

The purpose of this trip was to secure high molecular weight DNA from Poecilia reticulata. We are using 10X Genomics micro droplet based sequencing methods to sequence genomes and compare recombination rates between populations.

View down the mountain valley
View down the mountain valley

Catching fish with dip nets in a stream below a bridge
Catching fish with dip nets in a stream below a bridge

A red flower
A red flower

View down the mountain valley
View down the mountain valley

Spring 2015

In attendance: Ben Sandkam, Felix Breden, Matt Taves

The purpose of this trip was to compare differences in color vision and color preference across populations of guppies.

Sampling in the field
Ben takes tissue samples next to the stream

Hollis reservoir
A view overlooking the Hollis reservoir

Topographical maps of Trinidad spread on the table at the field station
Topographical maps of Trinidad spread on the table at the field station

Sampling in the field
Ben takes tissue samples next to the stream

Spring 2011

In attendance: Ben Sandkam, Felix Breden, Fran Breden* (undergraduate)

The purpose of this trip was to test for variation in color vision of guppies across populations, days and time of day in two watersheds.

Guppies (Poecilia reticulata) caught in a net
Guppies (Poecilia reticulata) caught in a net

Ben splashing in a stream
Ben splashing in a stream

Felix looking for fish with two dip nets
Felix looking for fish with two dip nets

Guppies (Poecilia reticulata) caught in a net
Guppies (Poecilia reticulata) caught in a net