BIOL 400 Lecture Notes - Lecture 10: Luca Ghini, Botany, Deism
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DESCRIBING AND ARRANGING ORGANISMS
A. BIOLOGICAL CLASSIFICATION
1. Important tasks of biological classification
compiling an inventory of diversity
providing a scientific name to each species and grouping
distinguishing species – but on what basis? What is the biological reality
that we want our species boundaries to reflect?
Or are species names merely conveniences, not reflecting any biological
before evolution – essentialism
after evolution – population thinking
fitting species into higher (more inclusive) natural groupings
2. Artificial vs. natural classification
artificial classification – group-defining attributes do not correlate with
natural classification – group-defining attributes do correlate with
Common names are useful but are not universally accepted. Sometimes many things have the same common name so this
makes diﬀerentiation diﬃcult.
Thought that diﬀerent species had diﬀerent essences.
What criteria do you want to use when naming species? What's the diﬀerence that we are trying to capture in the
Especially interbreeding populations. Members of a species are interbreeding members descended from a common ancestor,
this creates a boundary between species. This allows large variation within a species and as long as they meet the boundary
speciﬁcation then they can be the same species.
What to create a inclusive hierarchy. They started doing this before they realized they were mapping out evolutionary
Arranging things in a nested groupings.
Can put everything that is green in one class, but does not provide a biologically important group.#
This can have some uses like in identiﬁcation manuals. But doesn't tell you a lot about the organisms
Looking at relationships based on common descent. The more inclusive groups have a a more resent common ancestor
then the larger nest in which it sits.
Describing and Arranging Organisms - 2
B. PLANT SYSTEMATICS
1. The first modern works in natural history dealt with descriptive botany
Factors arose which compelled natural historians to go beyond the
Zoologists were interested primarily in function and adaptation.
Botanists were more interested in identification and classification, and
as a result of this they founded the modern science of biological
Background: the two most famous botanists of the ancient world,
Theophrastus (a pupil of Aristotle) and Dioscorides (a Greek physician
attached to the Roman army in the 1st century AD) each described
about 500 – 600 plants.
Descriptive botany and zoology was not done often in a systematic way until the scientiﬁc revolution.
Forests of norther Europe had diﬀerent organisms than Southern Europe.#
Also voyages to other continents brought back unusually plants and animals that people hadn't seen before. #
The invention of printing allows descriptive biology to be aided by illustrative ability.
Some were cultivated but most won't
Looked at animals to ﬁgure out what things did and were more interested in organic function. #
This aided evolution theory because because Darwin wanted to know how the functions of diﬀerent animals went
Interested in adaptation
A bit more descriptive and focused on identiﬁcation. This is the origin of biological systematics. #
This was useful because of the medical need to know diﬀerent things about diﬀerent plants and so classifying them was
It was mysterious why plants vary in their forms. The diﬀerent leaf types made people wonder about why one leaf was one
way while others were diﬀerent. It was hard to come up with testable hypothesis on the shapes.#
Functional biology was diﬃcult because of the range in structure types in plants.#
Interested in systematics. #
Functional botany can be hard to do, it's not evident why variation exists.
Describing and Arranging Organisms - 3
2. The botanists of the 16th century described approximately 500 plants
unknown to the Greeks, both medicinal and non-medicinal.
3. The invention of the herbarium (a library of dried and pressed plants) is
usually credited to Luca Ghini (1490-1556). Herbarium plant specimens can
be stored indefinitely, remaining in (approximately) their living condition.
4. For the botanists of the 17th century, the sheer numbers of described
plants (up to 18,000), and the awareness that many groupings of plants
were natural, resulted in information-management problems.
How can all this information be organized and accessed?
C. GEORGE-LOUIS LECLERC, COMTE DE BUFFON (1707-1788)
1. In his life, Buffon gained great fame and popular regard.
He published 36 volumes of his work Natural History, and another 8
volumes were published after his death. He was also the director of
the Royal Botanical Garden, which he turned into the greatest natural
history museum in the world.
The ﬁrst century of the scientiﬁc revolution. There were hints of natural groupings. As time went on the illustrations became more
detailed and useful Identiﬁcation.#
John Gerard (1545-1607) wrote a book on plants that contains descriptions of plants for the use of identiﬁcation and understand
potential uses. It was a standard book used at the time. Biological keys had not been invented at this time so accessing
information about plants was diﬃcult. As books like this cataloging plants indicated to people that some systematic system was
important for accurate identiﬁcation. #
Standard in the English speaking world as a herbal. The text was actually authored by a Dutch botanist who died prior to
publishing the book. Gerard then translated the book and published it.
Although some animals can be diﬃcult to preserve, plants are generally easier to preserve. A herbarium specimen is a
ﬂattened plant, preserving the specimen in the absence of water. This is a representation of a plant and is a record of
occurrence of a plants in speciﬁc location throughout history and allows understanding of population changes and
movements. These specimens are not immortal but degrade extremely slowly. Also this preserving method preserves DNA
so DNA analysis can be done on the specimens. #
Can use these herbarium specimens to reconstruct the historical environments of an area.#
The large amount of recorded plants became unmanageable to some systematic system of organization was important. #
This started as a collection, that turned into a systematic system, that lead into a map of organisms.#
A French Nobel man who lived the same time a linnaeus
He had an enormous public following Same name as pliny's
Also was a rural businessman and was a major land owner.#
Gifted writer and stressed the importance of literary style.#