For a guy who has spent most of his professional career developing, studying, and improving engineered systems, software, and applying mathematics to them, the idea of devoting a substantial part of the rest of his life to the study of bryophytes and, more specifically, the subdivision Bryophytina may seem an oddity. After all, I’ve launched a multiyear longitudinal field study of four sites with mosses the main act. Why?

It might begin that Bryophytina as a phylogenetic group originated during the Ordovician period, about 450 million years ago. They are suspected of having changed the Earth’s climate at the time. Nevertheless, as a botanical subdivision, they have seen everything, and have amazing adaptive capabilities, to extreme moisture, to dessication, to heat, to cold. They are both simple in their biological plans, yet innovative, and prudent if not wise.

There is also evidence mosses changed everything, weathering rocks during the Ordovician, when they are believed to have emerged, and that rock drew down atmospheric CO₂ which, at the time was around 3000 ppm, about 8 times what it is today:
P. Porada, T. M. Lenton, A. Pohl, B. Weber, L. Mander, Y. Donnadieu, C. Beer, U. Pöschl, A. Kleidon. High potential for weathering and climate effects of non-vascular vegetation in the Late Ordovician. Nature Communications, 2016; 7: 12113 DOI: 10.1038/ncomms12113.

And when I say they’ve seen everything, I mean everything. Mosses arose before the evolution of lignin-formation, so before vascular plants and especially trees. And, to quote Dr Neil deGrasse Tyson, “Earth was a different planet” for much of the time:

These are all taken from:

Bender, Michael L. Paleoclimate. Vol. 8. Princeton University Press, 2013.

via the Google online library.

And the above is from:

Parrish, Judith Totman, and Gerilyn S. Soreghan. "Sedimentary geology and the future of paleoclimate studies." Sedimentary Record 11 (2013): 4-10.

Present day mosses obtain many of their nutrients and water from the air, and raindrops, having basic or absent vascularization, some with rhizoids and relying upon cation exchange to obtain nutrients. They have amazing abilities to withstand both drowning and floods as well as desiccation. The moss Polytrichum, for example, rolls its laminae (leaves) up and together to retain water when it is drying out. Note: Laminae are generally but one cell thick!

Mosses come in amazing varieties, and have conquered every land habitat imaginable. In the Arctic they can be the dominant flora (Pope, 2016). They coexist with many creatures, yet are rarely grazed. They are for the most part, heartily communal plants, also coexisting with lichens and each other.

To me, I think the most intriguing aspect is as subjects for quantitative inquiry, counting, and measurement. Mosses are sessile, unless disturbed by water or fauna, such as squirrels scampering up trees. They make interesting photographic subjects, not only by themselves, but as part of a microhabitat. There is the opportunity to try to understand an ecology more completely than is possible in bigger niches, and perhaps to model.

Finally, it turns out we need to more carefully documenting their life cycles, and especially their phenology. On the latter, despite the urgings of Tuba, Slack, and Stark (2011) and others, it hasn’t been studied in depth. Longitudinal studies of the kind I’ve launched aren’t common. They don’t fit well within undergraduate or graduate timelines: They made need a decade or more of dedication, and that means dealing with transitions between students and problems with requiring originality in research, something which afflicts many fields. It seems to me that bringing the phenology of Bryophytina within the scope of the USA National Phenology Network is a reasonable way to proceed.