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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>ADDING VALUE TO BIODIVERSITY IMAGES THROUGH COMMUNITY ANNOTATION</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Greg Riccardi</string-name>
          <email>Riccardi@ci.fsu.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Andrew Deans, David Gaitros,</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Katja Seltman, Steven Winner</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>College of Information, Florida State University</institution>
          ,
          <addr-line>Tallahassee, FL 32306-2100 USA, 01-850-644-2869</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Neelima Jammingumpula</institution>
          ,
          <addr-line>Corinne Jorgensen, Peter, Jorgensen, Austin Mast, Karolina Maneva-Jakimoska, Debbie Paul, Fredrik Ronquist</addr-line>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>School of Computational Science</institution>
        </aff>
      </contrib-group>
      <abstract>
        <p>Morphbank, an on-line collection of museum-quality biological images, is an NSF funded project designed to facilitate the on-line collaboration of biologists from around the world [3]. Our primary focus is to aid in the collection and management of images that are useful in phylogenetic research. Morphbank users are actively collaborating on the creation of information that represents the associations among images and related biodiversity data objects. This paper describes the Morphbank annotation tool and data models and gives examples of how users create structured information in the system. Schematized annotation provides biologists with a flexible framework to create semantically-rich annotations using their own data models.</p>
      </abstract>
      <kwd-group>
        <kwd>Annotation</kwd>
        <kwd>association</kwd>
        <kwd>biodiversity</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. INTRODUCTION</title>
      <p>The discovery, identification, and documentation of biological
entities are time consuming and tedious tasks. The subtle
differences between similar species may be so minute as to
require the collaboration of several experts to identify. Each
taxonomic group has many experts who can assist in the
identification of specific organisms. However, with the increase in
the number of new organisms that have been discovered and a
decrease in number of senior specialists, identification and
curation of data have become more difficult. Often, it involved the
need for scientists to travel to the location of the specimens or for
specimens to be sent to the scientists for first hand examination.
This is still standard practice among most biologists today.
Morphbank contains information about organisms. Each image in
the system is associated with one or more specimens. Each
specimen is a representation of information about an organism.
Specimens are in turn associated with localities, contributors,
taxonomic concepts, and a variety of annotations.</p>
      <p>The design and development of the Morphbank system identified
several challenges in discovering and creating information about
images and their related objects.
 Finding images and specimens associated with a specific
species and genus,
 Finding and recording information about that image and its
related objects, and
 The discovery and recording of ad-hoc associations among
the various objects.</p>
      <p>Discovering and recording ad-hoc data is the most problematic. It
is particularly difficult to find ways that users can record
associations among objects.</p>
      <p>
        As long as data is well formatted and constrained to the database
schema then finding and retrieving it is simple. However, as
we’ve discovered, there is no practical limit to the amount of
information a scientist may wish to store with a particular
specimen. Most of the knowledge is contained in the memory of
these scientists or in hand written notebooks. Although it is
recognized that manual annotation is expensive and time
consuming it is nevertheless still essential in documenting
collaborative knowledge in biological systems [
        <xref ref-type="bibr" rid="ref1">2</xref>
        ]. Translating
and storing this knowledge in a searchable form is the challenge.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2. BACKGROUND</title>
      <p>
        Morphbank is an open Web repository of images serving the
biological research community. It is currently being used to
document specimens in natural history collections, to voucher
DNA sequence data, and to share research results in disciplines
such as taxonomy, morphometrics, comparative anatomy, and
phylogenetics. Morphbank can serve as a virtual reference
collection of named organisms or a resource for comparative
morphological study; new use cases are continuously added [
        <xref ref-type="bibr" rid="ref6">7</xref>
        ].
Each image in the database is associated with fully searchable set
of text information. Additionally images can be downloaded in
several different formats [
        <xref ref-type="bibr" rid="ref2">3</xref>
        ]. Understanding the background of
Morphbank is important to understanding the complexity of the
problem of collaborating with other scientists on the identification
and curation of biodiversity data.
2.1
      </p>
    </sec>
    <sec id="sec-3">
      <title>MORPHBANK OBJECTS</title>
      <p>
        Each object in the Morphbank system is uniquely identified and
includes a set of standard fields that assist us in cataloging the
location and type of each object, the identification of the user who
added the object, the date and time of creation, an optional
description of the object, and the last time the object was
modified. These attributes allow anyone accessing Morphbank
sufficient information to find and catalog data and associate
related objects. Each object is externally identified by a Life
Science Identifier (LSID) [
        <xref ref-type="bibr" rid="ref12">13</xref>
        ].
      </p>
    </sec>
    <sec id="sec-4">
      <title>2.2 MORPHBANK OBJECT</title>
    </sec>
    <sec id="sec-5">
      <title>RELATIONSHIPS</title>
      <p>Since each Morphbank object is uniquely identified, any object
can be the target of a stored reference. A single column within a
Morphbank table holding a foreign key may refer to several an
object of any type. Thus a collection object can be heterogeneous.
For instance, an annotation object may define an association
among images, specimens, locations, users, or even other
annotations.</p>
      <p>This flexibility allows for the creation of complex collections of
objects that can be shared with other users of the Morphbank
system. Although there are a series of predefined relationships in
Morphbank, the use of unique identifiers allows users to define an
unrestricted set of complex relationships of objects within the
confines of the system.</p>
    </sec>
    <sec id="sec-6">
      <title>3. BIOLOGICAL ANNOTATION</title>
    </sec>
    <sec id="sec-7">
      <title>REQUIREMENTS</title>
      <p>
        The users of the Morphbank database system have identified
several requirements for image and object annotation to be used
by authorized users of the system. These requirements are
consistent with the Specifications For Image Annotation On The
Semantic Web as described W3C in their draft document [
        <xref ref-type="bibr" rid="ref4">5</xref>
        ]. A
major restriction placed on Morphbank development was that the
annotation software must be accessible through the use of a Web
browser without the need to download an extensive set of client
based applications. This requirement was established because
research biologists frequently travel from one location to another
and many times only have access to a Web browser. Additionally,
annotations must be made in real-time and directly to the actual
data source to avoid update anomalies associated with multiple
copies of the data. Updates and annotations made by one scientist
must be readily available to other colleges for collaboration in a
timely manner.
      </p>
      <p>
        There has been considerable effort put into the development of
general purpose Web-based annotation tool sets over the past
several years. In their paper on Web annotations, Venu
Vasudevan and Mark Palmer [
        <xref ref-type="bibr" rid="ref14">15</xref>
        ] described an approach 6 years
ago on the development of a Web based annotation tool that could
be used to annotate documents over the Internet with just the use
of a Web browser. However, they discovered several limitations
in the use of Web browsers and of HTML as layout languages that
made digital annotations somewhat cumbersome. The increased
use of Javascript, higher speed communications, improved Web
interface standards, and increased browser capability have made
Web-based digital annotations more of a reality. However, there is
still no convenient method for making annotations on the sides of
Web pages as you would on paper documents [
        <xref ref-type="bibr" rid="ref7">8</xref>
        ].
      </p>
      <p>The problem of biodiversity annotation is that biologists have
increased the number of specimens they can gather but have not
increased their ability to catalog, identify, and study them.
Collaborations still include the exchange of physical specimens
and the manual annotations of the images using indexed cards and
paper documents. At the functional level, many users have
developed their own specific but proprietary solution to this
problem. Through the use of Morphbank and a Web based
annotation tool, we can solve most if not all of these problems.</p>
    </sec>
    <sec id="sec-8">
      <title>3.1 MORPHBANK OBJECT ANNOTATION</title>
      <p>A variety of annotation technologies allow users to add value to
images by creating associations between those images, text and
other digital objects. Morphbank takes this one step further by
making the associations into first class objects that can themselves
be annotated and associated with other objects. Morphbank also
allows associations to take on specific semantic characteristics
that constrain their meaning and thereby improve searching and
understanding.</p>
      <p>Image annotation is available in a variety of image management
Web sites. The simplest annotations are found in systems that
support attaching tags to images and other media. Flickr.com and
YouTube.com, e.g., allow users to add text attributes (tags) to
images and use those tags to support searching. FotoTagger.com,
among others, goes a step further and allows the tags to be
attached to specific locations on images.</p>
      <p>Blogging is another form of image annotation in which text
passages are linked to images, Web pages and other digital
objects. A blog entry creates an associate between its own text and
the linked objects.</p>
      <p>Annotea.org supports the creation of RDF attributes for image
tags. These attributes can be used to provide search inference
capabilities for users of image repositories.</p>
      <p>
        Another annotation strategy involves the development of
laboratory notebooks such as those under development at the
United States Department of Energy, National Collaboratories
under the guidance of Dr. Jim Myers [
        <xref ref-type="bibr" rid="ref10">11</xref>
        ]. These middle-ware
products present researchers, applications, problem-solving
environments (PSE), and software agents with a layered set of
application services that provide a finite set of capabilities for the
creation and management of meta-data, the definition of semantic
relationships between data objects, and the development of
electronic research records [
        <xref ref-type="bibr" rid="ref9">10</xref>
        ]. Users are able to record
associations between digital objects across and among projects.
Morphbank seeks to combine these ideas by allowing
incorporating an extensible annotation type system and by
systematically expanding the scope of associations by including
any objects referenced by globally unique IDs (GUID).
Morphbank was designed to allow users to take advantage of Web
service products to gain access to the data by conforming to
industry practices and standards but maintain the ontology of the
original data. Users will browse or search the Web site for
Morphbank objects using a variety of tools provided through the
Web site.
      </p>
    </sec>
    <sec id="sec-9">
      <title>3.2 BASIC ANNOTATION TEMPLATE</title>
      <p>An annotation is an assertion that a collection of objects are
related in a particular way. For annotation and search purposes,
the Morphbank object annotation tool provides a minimum set of
tools common to all annotation requirements. The tool uses the
terminology of the Darwin Core [1] biodiversity ontology
initiative. We strove to keep the tool-set as simple and as straight
forward as possible and to provide specializations that make it
easy for particular types of annotations to be created.</p>
      <p>Flexibility is particularly important because all annotations must
be made using only a Web browser. The template for the tool
defines several functional areas required for basic biodiversity
annotation and specimen determination.</p>
    </sec>
    <sec id="sec-10">
      <title>3.3 TYPES OF ANNOTATIONS</title>
      <p>Using the ability to store complex metadata with annotations
gives allows us to define associative semantic relationships with
ad-hoc data and other Morphbank data. The data model that
supports annotation is intended to be extended to incorporate
additional types as needed by users. The categories of annotations
in the current system are as follows:
 General: There are instances where users desire to make
some ad-hoc comments concerning a collection of images,
specimens or other objects. The requirement for this type of
annotation was made to allow maximum flexibility for
including comments, measurements, and other related data to be
stored and associated with the collection of objects. A very
useful example of a general annotation is a simple collection of
objects, much like a shopping cart, that can be stored,
organized, and labeled for later use.
 Image: As a phylogenetic database, images are vitally
important to the users of the system. Therefore, many of the
annotation types described in this section will apply specifically
to images. The types of image annotations are listed as:
</p>
      <p>Spot location on an image associated with the annotation.
The user will identify a specific spot on the image to associate
with a label, title, and paragraph description.
</p>
      <p>Circle associated with an area on the image.a The user will
place a circle encapsulating an area to associate with a label,
title, and paragraph description.
</p>
      <p>Rectangle associated with an area on image. The user will
place a rectangle encapsulating an area to associate with a
label, title, and paragraph description.
 Taxon Determination: Used for discussion concerning the
species or other taxonomic determination of a specimen. Users
will select a specimen and by using the associated images, make
a recommendation as to the specific genus and species
determination. Taxon determinations are extremely important to
the research activities of the primary users.
</p>
      <p>Phylogenetic Character and State: This type of annotation
will be used to organize physical features (called ―characters‖)
of organisms into objects of interest to research users.
Phylogenetic characters and possible values (states) of those
characters are associated with specific images, with species, and
with collections of species. In this type of annotation, the user
will associate an image or specimen in the database with
phylogenetic characters and states.
</p>
      <p>Relationship: Morphbank comes standard with predefined
data relationships. Relationship annotations allow the user to
define additional relationships associating Morphbank objects
with each other. User will select any two Morphbank objects
(image, specimen, view, location, publication, user, group, etc)
and then describe the relationship among the two.</p>
    </sec>
    <sec id="sec-11">
      <title>4. EXAMPLES OF ANNOTATIONS</title>
      <p>Specimen image annotation captures people’s knowledge of
species such as new observations, and disagreements with
previous annotations. Image annotation enables semantic image
retrieval and maintains a record of user comments concerning the
data. Furthermore, a collection of featured annotations provides a
way to assign species to a specimen. Image annotation associates
textual information to the specific region of an image to enable
semantic querying.</p>
      <p>Two technologies are frequently used: Text-based approach and
field-based approach. The former simply add keywords to the
whole image using natural language. However, keyword-based
retrieval returns irrelevant documents (i.e., low accuracy of
retrieval). A field-based method describes and retrieves an item
using one or more field-value pairs, thus improves the retrieval
precision. Figure 2 shows an image annotation of the field-based
approach. This annotations asserts that a particular portion of an
image (of a wasp leg) is a femur.
However, both text-based and field-based approaches store the
information in a plain text format. It is known that querying the
plain text is inefficient. Furthermore, storing annotation
information using only plain text is not suitable to satisfy the
higher level requirements for the system. Meaning and ontology
must be associated with the data. The heterogeneous data models
from different biologists and the diversity of association types
require frequent update and evolving data structures.</p>
      <p>The annotation of Fig. 3 asserts that the wasp whose leg is shown
has a particular feature, which is called ―femur swollen medially‖.
Such features are used by experts to categorize specimens into
taxonomic units (genus, species, etc.) and, after analysis, to
develop evolutionary models.</p>
      <p>Morphbank is using annotation and association technology to
collect information that is directly used in scientific research.
Each of the Morphbank objects related to the annotation of Figure
3—the image, the annotations, the related specimen, etc.—are
represented as first-class objects with globally-unique identity.
Thus the objects can be stored in collections, included in other
annotations, and referenced in external sites.
Mass annotations are possible as well. Figure 4 shows an interface
that allows a user to annotate each of a group of objects. In this
case, the user is preparing to comment on the species
identification, also called the determination of several botanical
specimens. This annotation interface has been developed to enable
a specific activity to be performed by experts on plant
morphology.
Creating the determination annotation sheet began with interviews
with domain experts and the evaluation of typical manual records.
Figure 6 shows a detail of the herbarium sheet of Figure 5 that
contains the information cards that are attached to the sheet. Two
cards are attached. The lower card is the primary information
about the specimen including who collected it, when and where.
The lower card also shows the species determination that was
recorded when the specimen was collected.</p>
    </sec>
    <sec id="sec-12">
      <title>5. PRELIMINARY RESULTS</title>
      <p>The Morphbank research team has been working closely with a
group of botanists at the Department of Biological Sciences at
Florida State University to use the annotation tool for the curation
of specimens from the Robert K. Godfrey Herbarium at Florida
State University. Figure 5 shows some of the Morphbank
information for a typical herbarium sheet.
The upper card shows a determination annotation that was added
to the specimen in 1983. J. Farmer of the University of North
Carolina agreed that the determination was correct.</p>
      <p>In pencil, between the two cards is second annotation. D. D. Ward
in 1983 also agreed on the correctness of the determination.
The Morphbank annotation tool is intended to allow the online
collection and dissemination of information like that shown in</p>
      <p>A major benefit of the Web tools is its support for distributed
collaboration. Before the sheets were
The annotation interface shown in Fig. 4 can be used to agree with
the recorded determination of the set of specimens, or to disagree
and select a different taxon. In this way the annotation represents
a qualitative evaluation of the recorded information. Fig 4 shows
that 19 annotations already record agreement (A) with the
determination.</p>
      <p>The results so far are very promising. Fifteen taxonomists were
asked to use Morphbank images of specimens from the Robert K.
Godfrey Herbarium at Florida State University to make digital
determination annotations for 50 specimens each. The scientists
found the online tools to be an excellent replacement for the
manual task. They were particularly pleased to be able to see the
results online and to be able to see the effects of this online
collaboration.</p>
      <p>An additional study of the feasibility of making determinations
from images in lieu of physical specimens was conducted by
bringing some of these experts to Florida. The study is ongoing.
We hope to be able to establish that digital representations of
these specimens are more than adequate replacements for the real
objects.</p>
    </sec>
    <sec id="sec-13">
      <title>6. CONCLUSION</title>
      <p>We have described an existing need in the biological community
to store and retrieve complex information on specimen and related
images. In creating a Web site that stores the elements common to
all entities in the Tree of Life, we have made biodiversity research
more effective.</p>
      <p>Our work in developing a tool that allows users to annotate
images via the Web using only the essential elements has proven
successful. The non-intrusive method permits biologists to mark
images without altering the original image, and share this
annotations with others in an easy and open format. Our hope is
that the work performed under this NSF grant by the Morphbank
project will provide the Tree-of-Life initiative with a stable digital
image database and annotation tool set that can be used by
biologists around the world.</p>
    </sec>
    <sec id="sec-14">
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