Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: How can one measure group cohesion? From individual organisms to their
  interaction   Measuring atomic and molecular interactions was one of the main objectives of
physics during the past century. It was an essential step not only in itself
but because most macroscopic properties can be derived once one knows
interaction strengths. At the present time, except for systems that can be
described as discrete networks (like the Internet network) our knowledge of
social and biological ties still remains very limited. An important step is to
develop experimental means for measuring social and biological interactions. In
this talk there are two parts. Firstly, we describe experimental evidence of
inter-individual attraction in populations of insects. Secondly, we focus on a
specific system, namely populations of Euglena gracilis, a green, swimming
unicellular organism, for which we try to determine individual and interaction
properties.

21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph