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Many analyses of ecological networks in recent years have introduced new indices to describe network
properties. As a consequence, tens of indices are available to address similar questions, differing in specific detail,
sensitivity in detecting the property in question, and robustness with respect to network size and sampling intensity.
Furthermore, some indices merely reflect the number of species participating in a network, but not their interrelationship,
requiring a null model approach. Here we introduce a new, free software calculating a large spectrum of network indices,
visualizing bipartite networks and generating null models. We use this tool to explore the sensitivity of 26 network indices
to network dimensions, sampling intensity and singleton observations. Based on observed data, we investigate the
interrelationship of these indices, and show that they are highly correlated, and heavily influenced by network dimensions
and connectance. Finally, we re-evaluate five common hypotheses about network properties, comparing 19 pollination
networks with three differently complex null models: 1. The number of links per species (“degree”) follow (truncated)
power law distributions. 2. Generalist pollinators interact with specialist plants, and vice versa (dependence asymmetry).
3. Ecological networks are nested. 4. Pollinators display complementarity, owing to specialization within the network. 5.
Plant-pollinator networks are more robust to extinction than random networks. Our results indicate that while some
hypotheses hold up against our null models, others are to a large extent understandable on the basis of network size, rather
than ecological interrelationships. In particular, null model pattern of dependence asymmetry and robustness to extinction
are opposite to what current network paradigms suggest. Our analysis, and the tools we provide, enables ecologists to
readily contrast their findings with null model expectations for many different questions, thus separating statistical
inevitability from ecological process.