Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Extinction, diversity and survivorship of taxa in the fossil record   Using data drawn from large-scale databases, a number of interesting trends
in the fossil record have been observed in recent years. These include the
average decline in extinction rates throughout the Phanerozoic, the average
increase in standing diversity, correlations between rates of origination and
extinction, and simple laws governing the form of survivorship curves and the
distribution of the lifetimes of taxa. In this paper we derive mathematically a
number of relations between these quantities and show how these different
trends are inter-related. We also derive a variety of constraints on the
possible forms of these trends, such as limits on the rate at which extinction
may decline and limits on the allowed difference between extinction and
origination rates at any given time.

2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
16
The categories of this paper are: stat