QUIZ 1
Topic 1: EVOLUTION
Zebra mussel invasion in the great lakes, relatively recent followed by a rapid
spread, major cause for concern for environmental and economic reasons. Depth of
knowledge does not extend much past that
Gregory – evolutionary biology, genomics and biodiversity science – NOT in
conservation biology or malacology (study of molluscs)
Formulating questions and using “biologists training to seek answers of them when they exist”
Search of primary scientific literature
o First step for scientists seeking info
Consultations with experts in the field
Hands on field work to properly understand how one studies mussel biodiversity in
freshwater systems
Initial observations
Gregory – Orillia, 100km north of Toronto. Tourist hot spot – two popular lakes
(Couchiching (north) and Simcoe (south)), also gateway to cottage country
Hawkestone – Orillia and Barrie – simcoe summers – water becoming clearer
o Quantity of particulate matter in the water column has been greatly reduced
o By product of huge abundance of zebra mussels
Filter-feeding activities cycle massive amounts of water every day
o no zebra in sand – no rocks or other native mussels nearby to attach to well
theyre developing
congregate on dock because sheltered from currents + other things
that may dislodge them – but anchored on strongly
sheer number of them – normally very few of any mussel in that area
attached to each other as well
people will cut their feet because theyre sharp
attachment and number – economic problems with invasion into
great lakes region
any solid place: boats, water intakes, industrial relevant equipment
, BIOL 1070 EVOLUTION WELL NOTED QUIZES
and other mussels
effects of infestation in Georgian Bay, Lake Huron, Sauble Beach (southern most point
of Bruce Peninsula)
o Sauble Beach
Separates Lake Huron and gerogian bay
Dead mussels wash up and affect quality of the beach – sharp
Extreme
density Finding More Information
Can impact our enjoyment of lakes
, BIOL 1070 EVOLUTION WELL NOTED QUIZES
Negative consequence – attach to any solid surface – menace to clog pipes and
cover docks, boats and industrial equipment
o Estimated that the economic damage+ efforts to control them = BILLIONS
Questions:
o Where did they come from
o When and where did they first arrive and how they have spread to quickly
o What impacts are they having on native fauna and ecosystem
o Why have they been so successful at spreading into new lakes and
You should always ask…
o Who is making the statement?
o Where did they get their information?
o Have they backed this up with references or data
o Are there alternative interpretations that the authors seemed to have missed
Good sources: national or provincial/state government agencies, regional,
provincial/state conservation society webpafes and websites authored by
scientists
o Fisheries and Oceans Canada, US Geological Survey
Interpret with caution: Wikipedia, blogs, newspaper
articles
BEST: original source. Science = peer-reviewed publications in scientific journals
o Peer-reviewed – reporting new information sent to at least 2 anonymous
experts in the field who provided critical comments on the reliability of the
research, the interpretation of data and the over all quality of the paper
o Peer-reviewed = may be accepted for publication “primary
literature”
Provides a filter to improve accuracy of scientific publications
Not perfect – just the first step really
Published, seen, commented on, even refuted by anyone in
scientific community
o Basically share their research with other
researchers What Do We Know?
, BIOL 1070 EVOLUTION WELL NOTED QUIZES
Reliable sources:
o Websites and books by scientists + primary literature
Zebra mussel (Dreissena polymorpha) = native to eastern Eurasia
o Black sea and Caspian sea
o Most likely transport across Atlantic in ballast water of ocean liner (larvae, some
suggest adults attached to ships)
o First reported in NA in 1988 in Lake St. Clair
o They spread rapidly throughout the surrounding watershed
o Not the first time – invaded western Europe in the late 1700s and early 1800s
o Second invasion by related mussel, quagga mussel (Dreissena rostriformis)
Remember to ask “how do we know this” about natural world
The Native Mussel Fauna
Evolutionary biologists = invested in diversity of species in particular habitats
o Zebra invasion – impacts that sudden changes have on species