Describing + Arranging Organisms Flashcards
What were 4 important tasks of biological classification?
- compiling an inventory of diversity
- labelling species and groups with scientific names
- distinguishing species and creating a method of distinguishing them - deciding what reality we want species boundaries to reflect, if any?
- fitting species into higher (more inclusive/nested) natural groupings
How were species distinguished before evolution?
essentialism - ‘essence is prior to existence’; groups are defined by characteristics (‘essences’) that are shared amongst only members of a group and that these characteristics were set before development and are unchanging (anti-evolution)
species have fixed characteristics that are unchangeable essence and based on ideal forms
How were species distinguished after evolution?
population-thinking model - a population of a species are a group of organisms that share features because they are descendent from a common ancestor NOT because of a common ‘nature’
this integrates change of characteristics over time
Define and compare artificial vs. natural classification of species
artificial classification: group-defining attributes do not correlate with other attributes = selecting unifying characteristics first and then grouping
- ex. habitat, colour, number or shape of leaves
natural: group-defining attributes DO correlate with other attributes = grouping organisms based on similarities and then identifying shared characteristics
- ex.
What 2 fields did the first modern works in natural history deal with?
botany and zoology
What factors arose which compelled natural historians to go beyond the ancient authors?
Advancements in travel allowed people to observe that different organisms existed in different parts of the world - European people were ‘discovering’ new plants and animals
print also allowed descriptive botany and zoology to be supplemented by illustrations
What were zoologists mostly interested in?
function and adaptation
How did the main interests of zoologists contribute to evolution theory?
understanding the function of animals always for better understanding of relatedness and why organisms might have certain structures
also notable differences in function/variability made them wonder why
interest in how the functions work together
adaptation is directly related to evolution theory
What were botanists mostly interested in?
identification and classification
Who founded the modern science of biological systematics? how?
botanists because of their interest in identification and classification of plants
Why was it more difficult for botanists to contribute to evolutionary theory than zoologists?
function, adaptation and the significance of variability in plants is not always as clear as it is in animals
Who were the 2 most famous botanists of the ancient world?
Theophrastus - pupil of Aristotle
and
Dioscorides -physician of the Roman army
How many plants did both these 2 ancient botanists describe?
they each described ~500-600 plants
How many plants did botanists of the 16th century describe unknown to the Greeks?
~500, medicinal and non-medicinal
Why was it important to classify and describe plants?
plants have medicinal applications
What was mysterious about plants?
they can vary in their forms (ex. different leaf types) and functional biology was hard to apply because plant species have so many different types of structures
Who invented the herbarium?
Luca Ghini (1490-1556)
What is a herbarium?
a library of dried, pressed, preserved, labelled and organized plant specimen which store plants in living condition indefinitely as a reference and resource for studying
What was the significance of the herbarium? What are the contributions of herbaria today?
a herbarium stores and preserves a representative plant of a plant species and includes a record of occurrence in location throughout history
used for studying botany
- track population changes and movements
now:
- preserved DNA so later analyses could be used to determine relatedness
- reconstruct historical environments of an area
What caused the information-management problems for botanists in the 17th century? What questions arose from this?
the immense volume of described plants (up to 18,000) and the awareness that many groupings of the plants were natural
this caused botanists to address the way groups were being organized - ‘how can all this information be organized and accessed?’ to reduce redundancy and ease accessibility for research
Who was George-Louis Leclerc, Comte De Buffon (1707-1788)? What was he famous for?
French nobleman
Famous during his lifetime, he published 36 volumes in his work “Natural History” and an additional 8 volumes were added posthumously
He directed the Royal Botanical Garden which became the greatest natural history museum in the world
What was Leclerc/Buffon’s famous work?
the 36 (+8) volumed Natural History
What were some of the topics in Buffon’s Natural History?
geology
minerals
origin of life
embryology
physiology
biogeography
functional anatomy
systematics
mammals
birds
anthropology
sociology
cultural history
general and theoretical articles
posthumously: reptiles, fish, whales
What were Buffon’s contributions to classification? How does this relate to today’s concept?
he believed that only the species level of classification could reflect a biological reality and that higher taxonomic levels do not - this is pretty accurate to the biological species concept
species can be distinguished based on reproductive behaviour