The resurrection plant can lose 95% of its water and still come back to life
Native to the Chihuahuan Desert, the false rose of Jericho can survive losing almost all of its water. In severe droughts, its stems curl inward into a tight, tumbleweed-like ball to protect its inner tissues, entering a state of dormancy where its metabolism virtually stops. Once rain arrives, the plant rehydrates and fully unfurls back into green foliage within just a few hours.
An Ancient Survivor of Arid Landscapes
In the dry, rocky expanses of the Chihuahuan Desert, which stretches across parts of the southwestern United States and northern Mexico, conditions for plant life can be exceptionally harsh. Rainfall is scarce, unpredictable, and often followed by prolonged months of intense drought. Most standard desert plants survive these extremes through deep root systems, water-storing succulent stems, or rapid annual life cycles that conclude before moisture vanishes. Selaginella lepidophylla, commonly known as the false rose of Jericho, adopts an entirely different evolutionary strategy: it tolerates losing virtually all of its internal water without dying.
Botanically, Selaginella lepidophylla is not a flowering plant or a succulent, but a lycophyte—a member of an ancient lineage of seedless vascular plants that includes clubmosses and spikemosses. Lycophytes reproduce via spores rather than seeds and have existed on Earth for hundreds of millions of years. While many modern spikemosses thrive in humid, shaded tropical forests, Selaginella lepidophylla adapted to extreme desert environments, developing a specialized desiccation tolerance that allows it to withstand prolonged, severe dry spells that would prove fatal to nearly all other vascular flora.
The Mechanical Physics of Curling
When drought sets in, Selaginella lepidophylla undergoes a dramatic structural transformation. As water evaporates from its tissues, the plant does not simply wilt and collapse. Instead, differential drying between the outer and inner surfaces of its branched stems creates mechanical tension that forces the fronds to coil inward. This movement draws the outer branches around the center, forming a tight, compact, spherical ball reminiscent of a miniature tumbleweed.
This coiling serves several essential protective functions. By curling tightly, the plant dramatically reduces its exposed surface area, slowing down any further moisture loss. More importantly, the outermost dry branches shield the delicate inner growing tips and photosynthetic tissues from direct solar radiation and scorching desert winds. In extreme conditions, the roots can loosen from the soil, allowing the dry ball to be rolled across the desert floor by the wind, which aids in dispersing the plant across new terrain until it finds a depression or moisture source.
Entering Suspended Animation
Underneath the physical curling lies a complex biological phenomenon known as anhydrobiosis, or life without water. For typical plants, severe dehydration causes cell membranes to rupture, structural proteins to denature, and toxic metabolic byproducts to accumulate, causing irreversible tissue death. Selaginella lepidophylla prevents this catastrophic collapse by shutting down its metabolic activity almost entirely, entering a state of dormancy where respiration and photosynthesis drop to undetectable levels.
To survive desiccation without losing structural integrity, the plant synthesizes protective compounds, most notably trehalose, a specialized disaccharide sugar. As water retreats from the cells, trehalose forms a glass-like matrix that stabilizes proteins, enzymes, and lipid membranes, preventing them from falling apart or fusing together. This molecular scaffolding holds the cellular machinery intact, effectively freezing the plant's biological architecture in place until water becomes available again.
The Mechanics of Rapid Rehydration
When rain finally arrives in the desert, the revival of Selaginella lepidophylla is rapid and striking. The dry, brittle tissues act like a sponge, drawing in moisture through capillary action and hydrating cellular walls before active biological processes even resume. As the cells absorb water and regain their turgor pressure, the physical strain that forced the branches inward is released, causing the curled ball to unroll flat against the soil.
This unfurling typically takes only a few hours. As the internal moisture content rises, the glass-like protective sugars dissolve, metabolic pathways switch back on, and the plant repairs any minor oxidative stress sustained during dormancy. The leaves restore their chlorophyll pigmentation, returning from a dull, dusty brown or gray to a vibrant green, and normal photosynthetic activity resumes as if the drought had never occurred.
Untangling the Roses of Jericho
The extraordinary behavior of Selaginella lepidophylla has led to persistent confusion with another famous drought-tolerant organism: Anastatica hierochuntica, often called the true rose of Jericho. Native to the arid regions of North Africa and the Middle East, Anastatica hierochuntica is an annual flowering plant belonging to the mustard family (Brassicaceae). While both plants curl into dry balls and uncurl in the presence of water, their underlying biology is fundamentally distinct.
When Anastatica hierochuntica dries out, the parent plant is actually dead. Its curling is purely a hygroscopic, mechanical response that shields its seed pods inside a dead woody skeleton. When rain falls, the dead branches uncurl passively, allowing raindrops to disperse the viable seeds onto moist ground. In contrast, Selaginella lepidophylla is a perennial organism that remains alive throughout its desiccation cycle, reviving its own existing tissues rather than merely protecting seeds for the next generation.
Significance in Botanical Science
Selaginella lepidophylla belongs to an exclusive group of organisms known as poikilohydric resurrection plants. Unlike homeohydric plants, which expend energy to maintain constant internal water levels through extensive root absorption and stomatal regulation, poikilohydric plants allow their internal water content to fluctuate directly with the surrounding environment.
The ability to tolerate near-total desiccation—losing up to 95 percent of relative water content and surviving intact for years—makes Selaginella lepidophylla an important subject of botanical research. Understanding the genetic, metabolic, and biophysical mechanisms that allow its cells to survive dehydration offers valuable insights into the fundamental limits of plant stress tolerance and the evolution of vascular adaptations in extreme climates.
Key takeaways
•Selaginella lepidophylla is a desert-adapted spikemoss (lycophyte) native to the Chihuahuan Desert that survives losing up to 95% of its water content.
•During drought, mechanical forces curl its fronds into a tight ball, protecting vital inner tissues while metabolic activity drops to near zero.
•Accumulation of protective sugars like trehalose prevents cellular collapse, allowing the plant to rapidly rehydrate, turn green, and resume photosynthesis within hours of rainfall.
•Unlike the 'true' rose of Jericho (Anastatica hierochuntica), which curls as a dead plant to protect seeds, Selaginella lepidophylla remains alive and revives its own tissues.