How to Make a Good Insect Specimen label … … and why.
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Transcript of How to Make a Good Insect Specimen label … … and why.
How to Make a Good Insect Specimen label …
… and why
Digital Specimen Data
• Wave of the future
• Specimen labels = data sink (relatively primitive to get that data, borrow specimens, visit collections, etc.)
• Specimen labels transformed to digital format = data that can be used by the global community for many uses, some we have yet to envision
• 3 main concepts– Projection– Datum– Coordinate system
Geographical Concepts
What projections do
Tissot’s Indicatrix of distortion
Rectangular projection
Geographical Concepts: Datum
Common DatumsNAD27 (North American Datum): system derived
from land-based surveys, using Clarke 1886 ellipsoid
NAD83: satellite-based system using the Earth’s center as a reference point; eventually adopted as GRS80 (Geodetic Ref. System 1980)
WGS84 (World Geodetic System 1984): mathematically refined GRS80 used by the US military and default for GPS
For most uses, NAD83, GRS80, WGS84 are equivalent
Geographical Concepts: Datums
Coordinate Systems
• Degrees, minutes, seconds39°25’06”N, 92°26’18”W
• Degrees, decimal minutes
• 39°25.1016’N, 92°26.2942’W
• Decimal degrees *** use this!!
• 39.41837°, -92.43824°
N = +, S = -, E = +, W = -
What is an acceptable georeference?
Point: A numerical description of a place that can be mapped,
and…Extent: that describes the spatial extent of a
locality (or collecting event),and …
Uncertainty: its associated uncertainties.
What is a Georeference? Placing a spot on a map
Insect Label: low vs. high quality1 mi. E MoberlyRandolph Co., Mo.July 4-5, 1972Coll. E. G. Riley
USA: MO: Randolph Co.1 mi. E Moberly, Hwy. 2439.44929°N, 92.40219°W(WGS84), +/- 200m
VII-4-5-1972, E. G. RileyUV light, secondary growth oak-hickory forest
Old style – w/o georeference
single label
Modern style – includes georeference
Often need a double decker (= two labels/spec.)
Two labels vs. single label:Pro: keeps footprint of label small (4 or 5 lines)Con: twice the work cutting and placing
Common Georeferencing Practices:or, … what will happen to locality
data from your old-style labels
• Geolocate • Used for locating points and giving uncertainties, editing those points and uncertainties, finding
new points from known points
• Google Earth / Google Maps / GPS / paper maps, etc.• Used for locating points
• Georeference calculator• Used for calculating uncertainties from known points via recommended “best practices” for
particular locality types (named place, offset-heading, etc.)
Demonstrate with examples:
Point –radius method
Out-Put from Geolocate Search
Geolocate results for …
Moberly, MO 1 mi. E Moberly, MO
* Note: Uncertainty resized to polygon
Output from Georef calculator forpoint at “1 mi. E of Moberly on Hwy.
24: Randolph Co., Missouri”
• 39.449941 lat• -92.406406 lon• 7225• (WGS84) World Geodetic System 1984 datum• decimal degrees• 3.98237• 4.489 mi. = maximum uncertainty radius (= ½ of linear extent) **
Note that collecting event assumed to have taken place within a ca. 9-mile wide circle
• 1 mi• 0.00001 degrees
Geolocate vs. Good Label
1 mi. E Moberly, Hwy. 24, MOUSA: MO: Randolph Co.1 mi. E Moberly, Hwy. 2439.44929°N, 92.40219°W(WGS84), +/- 200m
Google Earth view
Suggested Protocol forPreparing Good Labels
• Take GPS reading in field (especially if an obscure locality with poor landmarks)
• Run GPS coordinates in Google Earth / Google Maps to relocate point at middle of extent of the collecting event (CE).
• Calculate maximum uncertainty radius of CE (use ruler in Google Earth, etc.)
• Record coordinate source datum (GWS84)
Suggested Protocol forPreparing Good Labels, con’t.
• Review how to use a GPS (set datum, record GPS model etc, + GPS error with each waypoint)
• Review how to take distance measurements using GoogleEarth and GoogleMaps
• Create master copy of CE label (MS Word).• Cut coordinates from typed labels and paste into
Google Earth for verification: must double check• Review how to format labels (font size, line
spacing, etc.) for printing in MS Word. • Review need for quality paper & printer